Fellow, Joint Quantum Institute & Joint Center for Quantum Information and Computer Science; Physicist, National Institute of Standards and Technology; Adjunct Associate Professor, University of Maryland
By David Zierler, Director of the Caltech Heritage Project
April 6, 2022
DAVID ZIERLER: OK. This is David Zierler, Director of the Caltech Heritage Project. It's Wednesday, January 12th, 2022. I'm delighted to be here with Dr. Alexey V. Gorshkov. Alexey, great to be with you. Thank you for joining me today.
ALEXEY GORSHKOV: Thanks. It's fun.
ZIERLER: Alexey, to start I know this is going to be complicated. You have so many appointments. What is your current title and institutional affiliation?
GORSHKOV: Right. I'm hired by NIST which is a part of the federal government Department of Commerce. It's the National Institute of Standards and Technology. These are the people who pay my salary. That's my appointment. Now my duty station as a federal employee is at the University of Maryland where I have an adjunct appointment. It's an unpaid appointment as an adjunct. At NIST I'm a physicist. At the University of Maryland, I'm an adjunct associate professor in the Department of Physics and also in UMIACS which is the University of Maryland Institute for Advanced Computer Studies.
Also at the University of Maryland we have two quantum institutes (actually, we have more than two, but I'm not affiliated with the others). One is called the Joint Quantum Institute and the other one is called QuICS, Joint Center for Quantum Information and Computer Science. Both of these institutes are actually joint between the University of Maryland and NIST. That's how they were built up. I'm a fellow of both of these institutes. Yeah, so it's kind of complicated.
ZIERLER: Alexey, physically are you always in College Park? Is there ever reason to be in Gaithersburg or Boulder?
GORSHKOV: Well, now I'm mostly at home because of the virus.
ZIERLER: Of course.
GORSHKOV: Most people are teleworking. If not for the virus, I'm in Boulder only if I'm traveling. What would happen is maybe I would sit mostly in College Park because that's where my entire research group is—all students, all postdocs, they're all there. Some bureaucracy and also some great physics interactions happen at NIST Gaithersburg. When I just got here in 2013, I would go there once a week or maybe even sometimes twice a week. More recently, before the pandemic, it's been more like once every couple weeks to once every month. Something like that.
ZIERLER: Now you became an adjunct associate professor from being an adjunct assistant professor. Is that to say that you were granted tenure to some degree?
GORSHKOV: No. This doesn't mean anything. It's just like it was too embarrassing for them to call me an adjunct assistant professor since I've been there for so long. This means nothing.
GORSHKOV: My position is with the federal government. It's as permanent as these federal government positions can be although if the Department of Commerce runs out of money and there's—
ZIERLER: Reduction in force.
GORSHKOV: Exactly! Yes, yes! That's exactly what I was looking for. Exactly. Reduction in force, so I could be reduced.
ZIERLER: [laugh] Now being at the University of Maryland do you have opportunity to interact with students? Can you sit on graduate student thesis committees?
GORSHKOV: Yes. Exactly. Basically except for things like voting for various faculty things like promotions and hires, although even for hires they do ask us for input. Especially if it's a quantum hire they will ask us NIST people for input. Other than these things, I get basically all the important rights of a faculty member where I advise students, advise postdocs, apply for external funding. As far as my group members, students, and postdocs are concerned, they basically see very little difference between how my group is run versus how a group of a regular faculty member is run. They basically wouldn't know the difference.
ZIERLER: Alexey, you mentioned external funding sources. Is that to say that not all of your funding comes from NIST?
GORSHKOV: Yes. Absolutely. A small fraction comes from NIST. The rest of the funding comes from the Department of Energy, NSF, Department of Defense. These grants I apply for in my capacity as an adjunct professor at the university.
ZIERLER: Alright let's start at a broad level. What is NIST's role in this saga of developing quantum computers? Where do they slot in?
GORSHKOV: Now we're looking back at the history right? We're stepping away from what I do and stepping back. NIST has actually played an important role in this. To emphasize this, I think NIST has four Nobel Prizes related to quantum computing to various degrees. They're not in order. One is Dave Wineland. He has a Nobel Prize for basically controlling trapped ions, and trapped ion quantum computing is one of the most promising paths towards quantum computing. Then there is Bill Phillips who is here in Gaithersburg. He got a Nobel Prize for developing laser cooling, and this is what allowed people eventually to cool atoms to sufficiently low temperature so that you can eventually trap them in optical traps and eventually build quantum computers out of these neutral atoms. Then there's Eric Cornell who is at NIST Boulder who went a step further and got Bose-Einstein condensates out of neutral atoms and he also got a Nobel Prize for that. This is also an important technique for neutral atom manipulation. Finally, there is Jan Hall's Nobel Prize for optical frequency combs which is not so directly relevant. It's still relevant to not necessarily quantum computers, but it's maybe relevant to quantum networks, frequency converters, quantum clocks.
NIST played a very big role in the development of this quantum technology for computing, but also for networking and also for sensing. NIST does metrology; that's what it's about. Metrology is sensing, and quantum sensing is in my view one of three pillars of quantum technologies—computing, networking, and sensing. As I just said, NIST played an important role in all three of these and still does.
ZIERLER: Alexey, besides from the obvious budgetary constraints in the way that a biologist might want to work for NIH because that's where they would get all of their funding anyway, why would you need to or is it advantageous for you to apply for funding beyond NIST?
GORSHKOV: If I want to have a bigger research group, then I would need to apply for more funding. If I just stayed with whatever NIST gives me, depending on how you count I might just be working on my own. I might just have enough money to pay my salary, but that's it. If I want to have a research group—in fact, the way I was hired by NIST it was understood and it was promised that I would be a fellow of the Joint Quantum Institute. I was hired with the understanding that I will build a research group and will apply for funding.
ZIERLER: Beyond government sources—I'm thinking of the various public private partnerships: Amazon and Caltech, Google and Stanford. Are there any private companies that are partnering with the University of Maryland that are relevant for your research?
GORSHKOV: Actually, one thing I should mention that I probably should've said even earlier, I have the same type of deal that John Preskill has which is the Amazon Scholar position. I suspect that John's is also 8 hours a week. I have the same thing which is separate and independent from the work that I do at NIST and University of Maryland. It's 8 hours a week of work on something that's unrelated so that there's no conflict. There's a sense in which this Amazon Scholar position is a public-private interaction, but there is more. Maybe one example is Chris Monroe who was full-time at the University of Maryland, he recently moved to Duke although he still has an appointment at the University of Maryland and still has labs there. He has a company, IonQ, which became the first publicly traded quantum computing company recently. IonQ works on building trapped ion quantum computers. Of course, there was a lot of connection between the University of Maryland and IonQ. One example at least of the type of funding that has occurred is I know Chris has given some money for a quantum seminar for students and postdocs such that they can buy pizza for their quantum seminars. Things like this.
ZIERLER: [laugh] Pizza is very important. I know how important pizza can be.
GORSHKOV: Very important! Yes, yes. There are a lot of other companies around. I think Booz Allen Hamilton is giving some money to QuICS, the quantum information theory center. I think there was some fellowship paid by Booz Allen Hamilton. I think there are probably other examples of this as well, but maybe I'm not privy to all of these examples.
ZIERLER: Now can you talk a little bit about what you're doing for Amazon or is that all shrouded in secrecy?
GORSHKOV: Yeah, only the stuff that's publicly available. You can read a recent announcement about what Amazon does, and I'm helping that effort. I'm not allowed to say anything.
ZIERLER: I wonder if you can talk in a more general level if you feel like you're involved in a race. Like is Amazon racing against Google, is racing against IBM, is racing against Honeywell? Is everybody working toward one goal and it's a matter of who gets there first? Or are there really different goals, different conceptualizations of what quantum computers are, and what they might be good for?
GORSHKOV: Maybe I shouldn't…let me not get into this. I don't want to get in trouble. I should read exactly what's publicly available and what the party line is. I could comment on this, but I'm probably not…
ZIERLER: No problem. One thing that you probably can comment on—the various places that you're a fellow at the University of Maryland—for the outside audience I wonder if you might explain what the difference is between these very similar sounding organizations.
GORSHKOV: Yeah, that's easy.
ZIERLER: There's the Institute for Advanced Computer Studies, the Joint Quantum Institute, Joint Center for Quantum Information and Computer Science. How related are they? Are they really different?
GORSHKOV: That's a good question. It's maybe not so bad that there are many of them because, if all people interested in quantum at the University of Maryland and NIST were under just one big umbrella, it would be just this humongous organization that would just not be effective, not be able to do anything. JQI, i.e. the Joint Quantum Institute, was formed by a combination of condensed matter theorists at the University of Maryland and atomic molecular optical, or rather cold atom, experimentalists at NIST like Bill Phillips and his orbit. This was the Joint Quantum Institute. It's one of three premiere synthetic quantum matter experimental centers in the US, but also it included the condensed matter theorists from the outset. Since then other theorists as well. It doesn't really include many, if any, card carrying quantum information theorists of the type of people that John Preskill produces out of IQI.
The Joint Center for Quantum Information and Computer Science is much closer to what IQI used to be before there was IQIM. It's really quantum information theory. JQI is basically quantum experiments and quantum physics theory, such as condensed matter theory, maybe some AMO theory, but not quantum information theory. QuICS is quantum information theory. Now UMIACS, you can think of it as an interdisciplinary extension of the computer science department of the University of Maryland although it's still a separate entity. That's what you can think of it as.
ZIERLER: This is also going to be a complicated question given all of your affiliations. What are some of the main projects you're working on currently?
GORSHKOV: There's a lot of stuff that's going on. I have a big group; I have lots of collaborations. Historically I would say my group used to do a combination of atomic molecular optical physics and quantum optics which is actually my background. That's what my Ph.D. was in. Plus condensed matter theory, plus quantum information. It was a mix of these three. It's still a mix of these three except probably with more emphasis these days on quantum information just because of how much interest there is in various applications of quantum information both in technology and in other areas of physics and computer science. This is the bigger picture.
As far as specific projects, maybe the things that are easy to explain to an audience are certainly various technological applications of quantum that I mentioned earlier---they are definitely a big part of this. It's quantum computers, quantum sensors, quantum internet, and all aspects of these. How do you build them at the physics level? Your physics systems—atoms, molecules—how do you build it? Also all the way up to how do you actually use them in practice? A lot of projects are of this kind, but then there are also very fundamental physics projects. How do you apply, for example, computational complexity theory from computer science to understand large interacting quantum systems in physics? These are some of the examples.
ZIERLER: What are some interface opportunities you have with experimentalists or even engineers who would be tasked with building some of these machines?
GORSHKOV: Right. When I talk about JQI and QuICS and University of Maryland and NIST, I usually say that this is probably one of the biggest advantages that we have here is we have this very large concentration of both amazing theorists and amazing experimentalists. The other thing that I often say is that my theory group historically has been one of the most active in interacting with experimentalists. Experimentalists sometimes come to my group and say, "Hey we measured this thing. Can you explain to us what it is?" Or the other way around. We come to them and say, "Hey, we have this great idea. Do you want to try this?" My group has always been a bridge between these quantum experimentalists who work on systems like trapped ions, neutral atoms, superconducting qubits, and photons on the one hand and the various theorists on the other. My group does a lot of talking to experimentalists. It's very exciting to do this because, instead of just proving theorems and proposing things, you actually see experimental results about something that you've proposed. It's very exciting.
ZIERLER: Alexey, some really basic questions about the science. Of course, AMO physics, condensed matter, many body physics, quantum information—these are all discreet fields in and of themselves. At the center of this Venn diagram are the things that you work on. I wonder if you could explain what the value is in combining these fields for the projects that are most interesting to you.
GORSHKOV: That's obvious, right? It's always like this. When you combine a few different ideas or ideas from different fields, you are much more likely to generate something new and exciting. I mean that's just how it is. This is why actually quantum information has seen so much growth recently: because people realize that if you apply quantum information ideas to problems that condensed matter theorists have been studying for years, you actually uncover new things. Similarly, if you apply quantum information theory to problems high energy theorists have been studying for years, you also uncover new things. Marrying different disciplines is always exciting and productive.
ZIERLER: Physics is always about the interplay between experiment and theory. For you, given how closely you work with experiments, where are the theorists out in front of the experimentalists? Where are the experimentalists leading the theorists?
GORSHKOV: There are examples of both. As I said, sometimes experimentalists just say, "That's what we can do. That's what we did. Here's our measurement. We scanned this parameter. We saw this very surprising bump. Where's it coming from? Explain." Or it can be totally different. It's could be like, "Here. We've proposed this entire path for realizing something really beautiful and complicated." And experimentalists are just way behind, and they're just realizing one tiny little part of that. It happens both ways. The exciting thing is I guess what has happened recently is there has been much more convergence.
It used to be that quantum experiments were of roughly two flavors. The first flavor was condensed matter experiments which were often very dirty and difficult to understand, and condensed matter theorists would argue over and over with each other about how to explain these experiments. At the end, none of them would even win because the experiment is so messy that there's maybe not even the right answer. It's just these big, difficult to control systems. The second flavor was AMO experiments. Some AMO systems were classical. People studied classical optics, classical nonlinear optics, things like this. Then AMO experimentalists learned to control individual atoms, and then it was pretty and quantum, but boring from the point of view of many body physics. It was not a many body physics problem. It was just single atoms, single photons. These experiments were very easy to describe theoretically in some sense.
Now finally people are able to put many of these atoms, many of these ions, many of these photons together in a controllable way which of course allows you to build a quantum computer. That's why all of this stuff is happening. It's also allowing you to study all of this controlled many body physics that in the past was studied in these dirty, uncontrolled, condensed matter systems. Very exciting.
ZIERLER: I love asking this question because you get as many answers as there are people to answer them. At a basic level do we have quantum computers yet? Or is that concept still far out in the future?
GORSHKOV: It depends on your definition. You could imagine that you made two quantum bits and you got them to interact with each other—you have a quantum computer that computes on two quantum bits. It's just not a very useful quantum computer. I mean, I'd say yeah. We have quantum computers, but not yet useful quantum computers that can answer something of prior interest that we've asked them to answer and that they have answered. This hasn't yet happened, but we hope that we're on the cusp of something like this.
ZIERLER: How do you define useful in the context of a quantum computer breakthrough?
GORSHKOV: It's again fuzzy. It's something that somebody would care about. There's this general hope and belief that possibly one example of this would be quantum simulation. Actually, we have this NSF funded Quantum Leap Challenge Institute at the University of Maryland. It was just funded this past year. It's between University of Maryland, but also a lot of other universities on the East Coast. The goal of this Institute is basically to construct useful quantum simulators.
The idea is that quantum computers are particularly good at simulating other quantum systems, and you can use quantum computers to answer questions about other quantum systems from chemistry, from material science, from high energy physics. This would be one example. Some chemist or some material scientist or some high energy theorist really wants to learn something specific about their system. They can't do this because the system they have is too messy, too difficult to control. They just can't answer the question. Then somebody simulates that system on a quantum computer and answers it for them. That would be a useful thing. At least initially, it likely won't be useful in the sense that there won't be millions of dollars associated with answering that question, but some sort of chemist or material scientist could just be very happy. Eventually, there could also be technological reasons. Maybe the question the quantum chemist is asking, maybe it's related to some drug. Then there could also be business implications.
ZIERLER: I wonder if one way of defining usefulness is negative. In other words, are there particular things that we see in classical computing that are limited for which theoretically quantum computers would just simply do a better job?
GORSHKOV: Just what I said. This is why quantum simulators are a particularly useful application because we know that, if you just naively try to describe a quantum system using classical resources that try to program the evolution of a quantum system on a classical computer, essentially no one believes that we can do this efficiently in full generality. That's why doing this on a quantum computer is a very useful thing to do.
ZIERLER: What about the idea that predefining usefulness gets us only so far? And it's about the basic science and achieving a quantum computer and then there might be big surprises as to applications or what it might be used for?
GORSHKOV: Sorry. What exactly are you asking?
ZIERLER: The question is in terms of research motivation, in terms of all of the resources that are being put into this effort, is part of simply achieving the technology and being open-minded about what it might be useful for at that point and not before?
GORSHKOV: Sure. You're saying that we don't yet know what all the applications are. I think this is fair to say. Yes. Some applications we know, and most applications that we know require this full largescale fault-tolerant quantum computer which we will not get too soon. Then there are applications that seem to be happening possibly, hopefully sooner, like this quantum simulation. Some are yet to be found, if that's what you're asking. I'm not sure I'm exactly answering your question, but yes.
We don't yet know the full scope of the applications of quantum computers, and that's one of the reasons it's so exciting. There are a lot of people who work on quantum algorithms which are algorithms that can be run on quantum computers. New algorithms are discovered all the time. People used to think that only certain kinds of differential equations could be sped up if you have a quantum computer versus classical solutions of these equations. There was a recent development that certain other kinds of differential equations could be solved more quickly on a quantum computer. It's all evolving rapidly.
ZIERLER: You mention materials, chemistry. As a physicist do you have—even if it requires some imagination—an idea of how quantum computers might be useful for solving some of the big mysteries in physics: quantizing gravity, moving beyond the standard model, model high-Tc superconductivity. Do you think along those lines as well?
GORSHKOV: Yes. Absolutely. Right. An example of this is, in this quantum simulation center, we have colleagues who are nuclear physicists, and they're really interested in understanding the microscopic properties of the world we live in. The Standard Model describing the world is a non-Abelian gauge theory, so nuclear physicists are interested in understanding such theories. It's very important that we can ask some very specific questions and hopefully in the future we'll be able to ask quantum computers to answer these questions for us. All the things that you mentioned. Materials, sure. High temperature superconductivity—possibly. The idea would be—people have talked about this for a long time. People are a little bit sick of talking about it, but that's the idea. There's this high temperature superconductor. First off, you have to understand how it works. What we do, we write down the model, but we don't know how to solve that model. What do we do? If we had a quantum computer, it could help us answer some questions about that model and then it would verify whether it's a good model or not. Hopefully then maybe we can do various tweaks to that model on our quantum computer, our quantum simulator, and this will tell us maybe what to do in the material science world to prepare a high temperature superconductor with a higher critical temperature so we get a room temperature superconductor. People have talked about it so much that it's a little…people don't like talking about it anymore. And, in any case, I'm not an expert at all on high temperature superconductivity.
ZIERLER: [laugh] Alexey, for you personally, for the group that you're building up, this is a very large and rapidly growing field. What do you see as yours and your group's specialty or area of expertise or research focus that might be understood slotting into this overall effort, this collaborative effort to create quantum computers?
GORSHKOV: Right. There is a meta-answer which is the stuff that I mentioned that we try to integrate different disciplines—condensed matter, AMO, quantum information—and try to bridge theory and experiments. That's a meta-answer. As far as specific research directions I can say many things. For example, we do a lot of work on sensing including distributed sensing.
ZIERLER: What is distributed sensing? What does that mean?
GORSHKOV: When you have a network of sensors that are sensing some spatially varying field and that somehow work together to answer some interesting question about the field that you're sensing. That's one example, but there are many more. For example, something that I had mentioned before that I really like is the application of computational complexity theory from computer science to understand many body problems in physics. That's another thing that I really like working on. Another example of something else that I've worked on quite a bit and I still enjoy is more on the physics side of things—but it has applications in quantum networking—is making photons interact. Usually photons just go through each other, but maybe you want to make a light saber so then you have to make them interact. We're doing some work on that. These are just examples; there are lots and lots of examples. We try not to become too narrow. The more ideas are floating around I feel like the more likely that we'll find something particularly exciting.
ZIERLER: Alexey, we've engaged on all of the interesting things happening right now. Let's go back and develop the historical narrative a little bit. Even as an undergraduate at Harvard were you thinking about quantum information, quantum theory at all? Was that sort of your interest right from the beginning?
GORSHKOV: Right. Yeah, exactly. The title of my thesis is—let me just make sure I get it right—Novel Systems and Methods for Quantum Communication, Quantum Computation, and Quantum Simulation. Just the stuff that we talked about.
ZIERLER: Yeah, but that's your doctoral thesis. I'm talking about as an undergraduate when you started.
GORSHKOV: Oh! As an undergraduate…
ZIERLER: For example, in 2000 this is when John Preskill is starting to write these amazing papers. Did that register from the beginning or that came later?
GORSHKOV: No. What did I know as an undergraduate? I'd just go to my classes, play badminton, dance ballroom, and row on the crew team.
GORSHKOV: There was no time during the school year to engage in any substantial research. I started college in 2000. The summer after my first year I worked in the high energy experimental lab. I was gluing some muon detectors for the ATLAS Experiment which eventually detected the Higgs boson. I just did some really silly things that were really small. Then next summer I did some math research at the genomics center. Only after my junior year, I did research at MIT in the Research Experiences for Undergraduates program with David Cory who's since then moved to Waterloo. That was on NMR quantum computing. That's when I guess it was probably the first time I found out about quantum computing. It was very exciting. I learned a lot from David. I learned more from my future advisor, Mikhail Lukin, who was teaching one of the classes I was taking as an undergraduate. The combination of the two of them was how I learned something about quantum computing. It seemed exciting, but it was also the only thing I knew at that time, I guess.
ZIERLER: You were exposed to a lot already at that point. Why quantum computing? Why did that speak to you?
GORSHKOV: I wasn't exposed to a lot. As I said, I think that's the only thing I knew. That was the only physics. Gluing these tubes for a muon detector wasn't physics. I think I was mostly controlling the temperature sensor in the room where the gluing was happening, so I didn't get to do any physics. The Research Experiences for Undergraduates with David Cory was really my first exposure to real physics research, and I happened to be lucky that it was actually on quantum computing. I think I just got lucky. I definitely didn't choose it from a bunch of other exciting things. That's all I knew.
ZIERLER: Why stay at Harvard for graduate school? Did you think about going elsewhere?
GORSHKOV: Yes. Let's see. There were maybe a few considerations. One was, as I said, I hadn't really done much useful physics research at Harvard at that point. I was taking classes but the only real physics research that I did was at MIT on this Research Experiences for Undergraduates. This thing that I did for muon detectors, it was not physics. It was controlling temperature sensors. So it's not like I'd be doing the same thing if I stayed. I hadn't really done any physics research.
The other consideration was that I was originally born in Russia. My parents brought me from Russia to Boston in '97 when I was 15. That move was pretty stressful and somehow enough. I was happy not to have to move again too soon. That played a role. I thought that working with Mikhail Lukin who I ended up working with was really promising. The combination of these things, and I really liked it at Harvard.
ZIERLER: What was Lukin working on when you first connected?
GORSHKOV: His background is quantum optics. Again, exactly the stuff that I also started working with him on. One of the things that he was famous for originally was quantum memories for photons, which is actually an important component of quantum networks, which is one of these three pillars of quantum technologies these days. That's the stuff that he originally started working on and also the stuff that I started working with him on when I joined the group.
ZIERLER: How did you go about developing your thesis?
GORSHKOV: It was not very a priori planned. You just work on one project and then you're exposed to a bunch of exciting ideas and then you just grab the next exciting idea and write a paper on that. When you're done with this or in the middle of doing this, you grab the next idea. It was not a preplanned process. I try to follow a similar strategy these days with my group members as well.
ZIERLER: What were the exciting ideas at that point?
GORSHKOV: I'm not sure I'll remember many or most of them or all of them, but it started with quantum memory. We understood something about quantum memories.
ZIERLER: What does that mean—quantum memory?
GORSHKOV: It can mean different things, but what I meant was memory for photons. Photons carry information in quantum networks from one node of the quantum network to another. Eventually you want to catch this photon and convert the quantum information stored in this photon into matter, into the memory. Quantum memory for photons is essentially this interface that allows you to catch a photon and store it in the matter. It's part of a quantum network. This was one of the first things I worked on.
Another example was being able to better control and better cool polar molecules which are actually another system that's a good candidate for quantum computing, and people are working on this. Another project was on thinking about various types of atoms that can be useful for quantum computing and quantum simulation. People used to work with atoms only from the first column of the periodic table, but while I was a graduate student it became popular to work on the second column of the periodic table. These atoms are different. They have two outer electrons instead of one. And having two outer electrons instead of one turns out to be advantageous. We wrote some papers on that, how this can be used for quantum computing and quantum simulation. The list keeps going, but these are some of the things.
ZIERLER: What were the principal conclusions of your thesis?
GORSHKOV: I don't think there were any principal conclusions. It was just lots of exciting ideas for how to advance quantum networking and quantum computing and quantum simulation in a variety of different systems. There was no big overarching principle other than try to make progress.
ZIERLER: Beyond Lukin who else was on your thesis committee?
GORSHKOV: It was Charlie Marcus who's since then moved to Copenhagen and John Doyle who is still at Harvard. I hope I'm not forgetting somebody. I think it was just the three of them.
ZIERLER: Good defense? Good experience at the oral defense?
GORSHKOV: Yeah. I think at most places—at least the places I know—the defense is kind of a formality. You're told everybody knows in advance that everything is going to be OK.
ZIERLER: There's always reality and hype in quantum computing. As you defended and were thinking about next opportunities…you talked earlier about hopefully we're on the cusp of something big. What did that feel like around 2010? Did it also feel then like quantum computing was on the cusp of something big? Is that a perennial feeling in the field?
GORSHKOV: Maybe to some degree. Of course, things were very, very different. We just started to believe that maybe indeed—not me, but other people more advanced than me at that point—maybe there is no fundamental road block to developing some of these technologies, especially quantum computing. The progress that has been made since then is absolutely unbelievable. We still haven't done anything useful with quantum computers, although you could say that some useful things have been done in some sense with quantum networking and quantum sensing. Those have already very much produced results.
Similarly on the way to building quantum computers, we've learned to control all of these quantum systems. By controlling these quantum systems, we've also learned lots of absolutely amazing physics. Even if quantum computers were not to pan out—which I think they will—we still learned a lot of amazing stuff. We've contributed to the development of other technologies. If you control a large quantum system, it can be a sensor too. It can be a clock or it can be a magnetometer or it can be a node in a quantum network. All of these things, they feed onto each other.
ZIERLER: This idea, Alexey, that…2010 you defend the thesis. There's just this beginning notion that these roadblocks that were assumed to be there might not be there. First of all, are we talking about theoretical or experimental roadblocks?
GORSHKOV: I'm also not sure necessarily that people assumed that there would be these roadblocks. Also, I'm not even sure I'm the best person to comment about what the experts were thinking back then because I was just a student. People were worried and some people are still worried, although I think there are fewer of them and they're not as vocal. People were worried that maybe we would never be able to overcome errors in quantum computers. That maybe as we build bigger and bigger computers, the errors will become scarier and scarier, and we will never be able to deal with them. More people are now convinced that that's not the case. The people who were very vocal back then about this maybe are not as vocal now. I guess there were maybe questions about whether the technology will develop sufficiently. There have been tremendous advances. One of the most noticeable things is people have learned to trap neutral atoms in individual traps and they can just rearrange these atoms in any way they want. It's truly this amazing stuff. There have been a lot of advances and perhaps some things that were believed to be experimentally challenging before have proven to be not as challenging, but there are still challenges.
ZIERLER: Was quantum error correction something that you worked on in graduate school?
GORSHKOV: No. I didn't work on it in graduate school.
ZIERLER: Totally different field.
GORSHKOV: Yeah. I didn't work on it in graduate school, and I only started learning a little bit about it while I was a postdoc at Caltech because that's what a lot of people there worked on, including John. I'm still learning about it. In fact, until recently we didn't really have a lot of quantum error correction expertise here in Maryland at any of these centers. Not a lot—I mean, people knew. But recently we've gotten quite a few new hires who are experts. Daniel Gottesman who is hopefully somebody else you're going to talk to, he's of course an inventor of some of the most powerful error correction methods. He's now here. Two younger new hires, Michael Gullans and Victor Albert. Victor Albert just came from Caltech as well. They also know quite a bit of error correction. I'm not an expert; I'm just learning. But it's crucial; it's very important.
ZIERLER: One great way to survey where the field was at that point are the opportunities—what was exciting, where you could've gone next. The first question there after you defend—why stay at Harvard for a half year?
GORSHKOV: Oh. This was just because most postdocs start in September.
ZIERLER: You just needed a place to hang out.
ZIERLER: Did you do anything productive for your postdoc?
GORSHKOV: Sure. Of course. I just continued doing the stuff that I was doing. I could've also defended a half year later, but defending a half year earlier allowed me to switch from a graduate student salary to a postdoc salary.
ZIERLER: No reason to delay that development. [laugh] Where else had you considered besides Caltech?
GORSHKOV: For postdoc, I was considering coming here actually, where I am now. There was also University of California, Santa Barbara. I feel like there may have been something else. But at the end it was between Caltech and coming here where I ended up now.
ZIERLER: Were you following at all in terms of IQIM's stature in the field, or how much collaboration there was at conferences? Were you aware of IQIM's reputation? Was that an exciting prospect for you?
GORSHKOV: There was no IQIM.
ZIERLER: IQI, I should say.
GORSHKOV: There was IQI which was quantum information theory. This was certainly exciting and this was the reason why I was hoping to go there to be with these quantum information theorists. Yes.
ZIERLER: Well, that's a good place I think to pick up until tomorrow.
[End of Recording]
ZIERLER: OK. This is David Zierler, Director of the Caltech Heritage Project. It's Thursday, January 13th, 2022. I'm delighted to be back with Professor Alexey Gorshkov. Alexey, it's good to be with you again.
GORSHKOV: Yeah. It's great to be here. Thanks.
ZIERLER: Alexey, to set some context. On your way to your postdoc at Caltech did you have a plan of what you wanted to do once you got to Caltech, having some idea of what was happening at the IQI? Or you came more open-minded, you wanted to see what was going on, and then make that decision?
GORSHKOV: There was a little bit of both. As you go for your postdoc you generally write a research statement or a set of simple research proposals, so I wrote some stuff and I had some plans. Before coming, before accepting the position, I actually came for a visit and I met with some people there. Some ideas were generated that way.
ZIERLER: Is that where you first met John Preskill? On that first visit?
GORSHKOV: Had I met him before…yeah, maybe. But this may have been the first time we actually talked although I'd been to his talks before. He gave a colloquium in the Harvard physics department at some point that was very cool, I remember, on topological quantum computing. This may have been the first time. To your question, it was a combination of the two things. I had some plans that I thought would work out and some of them worked out and I also was open to new ideas and that also happened.
ZIERLER: In terms of the ideas that you came in with what were they? What was exciting to you at that point?
GORSHKOV: I remember things I wrote about were related to things we discussed in our previous discussion. One of my areas of expertise—and it still is actually—was knowing the different physical systems that can be taken advantage of for various quantum technologies including quantum computing. Some of the things I wanted to work on were thinking about what polar molecules, for example, can give us as far as quantum computing and quantum simulation go.
ZIERLER: Polar molecules? I'm not familiar. What is that?
GORSHKOV: Polar molecules. Yes. These are neutral molecules as opposed to charged and they're diatomic—these are the ones I have in mind—made of two different atoms so that the electronic cloud is distributed unevenly. As a result there is an electric dipole moment attached to the axis that's connecting the two atoms in the molecule. When I was just starting as a postdoc, this was a relatively young field with some exciting early results, and we were thinking about what can be done with this. This field has developed since and we've indeed made some progress. There were other ideas in that research proposal. I mentioned these atoms of the second column of the periodic table; I wrote some stuff about that as well. I think there were other things as well that I can try remembering, but honestly I probably don't even remember.
ZIERLER: What were your initial impressions of Caltech on your first visit there before you joined?
GORSHKOV: It was great talking to everybody. Everybody was super nice. One thing that I found interesting was that Caltech condensed matter theorists are somehow some of the nicest condensed matter theorists in the world that I've ever met.
GORSHKOV: Condensed matter theorists are often or sometimes known for being tough. These guys were somehow…I found that Caltech put all the nicest condensed matter theorists together in their condensed matter theory department. This was one of the impressions.
ZIERLER: How closely aligned were the condensed matter theorists within IQI? Were they all working together? Is that why you got to know them?
GORSHKOV: When I just got there—this is one of the stories I can tell—there was IQI which was quantum information theorists. Then there were condensed matter theorists on the other side of campus. Then there were AMO experimentalists like Jeff Kimble who were at yet another place. I would say that there weren't as many interactions between these three groups of people—quantum information theorists, condensed matter theorists, and AMO experimentalists—as would have been nice. There weren't enough interactions.
ZIERLER: Was that your experience at Harvard, that they were more integrated there?
GORSHKOV: To some degree. What made this interaction eventually work is that, during my first year at Caltech, IQIM got started.
GORSHKOV: IQIM was the thing that pulled everything together. Things really dramatically changed.
GORSHKOV: Everybody started talking across all three of these disciplines. It was really exciting to witness that.
ZIERLER: Were you there during this decision-making process to add the "M" onto IQI? Did you witness these things?
GORSHKOV: It was not a decision-making process. This was a grant application process.
GORSHKOV: It was an NSF grant. I think the process was led by Jeff Kimble and John Preskill, and it was a huge effort. There were at that time three other similar centers. One is the Joint Quantum Institute where I am now. Then the Center for Ultracold Atoms at Harvard and MIT where I was before coming to Caltech. And finally JILA in Boulder which I was also very familiar with. There were these three quantum NSF Physics Frontier Centers that already existed at that time. I knew that they worked really well at pulling people together and making them talk about quantum. John and Jeff went on this mission to get this fourth center which is quite challenging. Why would NSF fund a fourth quantum center? But they won it. It was very exciting.
ZIERLER: What do you think the winning argument was to make that case for a fourth center?
GORSHKOV: It was different because it was focused on quantum information. These other three centers were to some degree AMO-ish, atomic molecular optical physics centers with experimental and maybe condensed matter physics focus, while Caltech really was able to offer that quantum information theory from IQI. This was the difference. It was more of a quantum information theory flavored Physics Frontier Center.
ZIERLER: Alexey, given you were there during this transition is your sense more that IQI expanded into IQIM or it really became something new, different than what IQI was before?
GORSHKOV: It became something new. IQI was just quantum information theory. IQIM is this bigger entity that includes experimentalists, condensed matter theorists. Of course, IQI was important.
ZIERLER: Did that make it more in your wheelhouse given what you were interested in where you were coming from Harvard?
GORSHKOV: Yes. When I arrived at Caltech, there was not as much connection. I was trying to force these connections. That's what I had been doing in graduate school and what I do now. That's what I was trying to do as a postdoc. To talk to condensed matter theorists, quantum information theorists, experimentalists, and I was that bridge. I had Caltech graduate students come to me and say, "I like the stuff that you're doing. How would I do similar stuff?" I'd be like, "I don't know. Maybe you should be jointly advised by John Preskill and Jeff Kimble because there's no single principal investigator at Caltech who does this kind of stuff."
GORSHKOV: Once IQIM was started, this was much easier to do because they started talking. Everybody started talking to each other much more. People found common interests.
ZIERLER: Alexey, to go back to my original question about the ideas that you came in with and the ideas that you developed. Particularly once we have IQIM how did that change things for you? What you wanted to work on? What was possible to work on?
GORSHKOV: It became easier. I would just see condensed matter theorists and AMO experimentalists. I would just see them more often. I was sitting in the Annenberg Building which is where IQI was. This is the quantum information theory building, or rather the computer science building which includes quantum information theorists. AMO experimentalists and condensed matter theorists were in a different building. Once IQIM was established, there were, for example, now regular IQIM talks. There would be a talk and afterwards people would hang out, eat some snacks—sushi or stuff like that. I would get a chance to interact much more naturally with these other people. This helped generate new, exciting ideas that otherwise I wouldn't have been able to generate.
ZIERLER: Because quantum computing, the successful application of quantum computing, will need the merging of theory, experimentation, and even engineering, did you see in real time the creation of IQIM as a concrete step in that direction?
GORSHKOV: Yes! Absolutely! Exactly.
ZIERLER: Explain how. How did that come together? How did that become apparent for you?
GORSHKOV: People just started talking to each other. It's a two way street. People talking to each other helps build whatever—a quantum computer—but also the other way around. As you're trying to think about these different quantum technologies, it helps develop these fields. It's a two way street. I'm not sure that came through clearly…anyway.
ZIERLER: [laugh] For you what was the research culture like at IQIM? Who would you be collaborating with? Was it sole author papers? Were you writing with other postdocs? How did that work?
GORSHKOV: IQIM or IQI?
ZIERLER: IQI initially and then IQIM once it was developed because you were there for all of that.
GORSHKOV: IQI wasn't that big. It was John Preskill as the main PI and then once in a while Alexei Kitaev would come and hang out with that crowd. Then there were a lot of excellent postdocs and a lot of excellent students. I would hang out and collaborate with those students and postdocs. I was particularly interacting with one student, Michael Beverland, for example, quite a bit. That was good. I was learning quite a bit from postdocs. In particular, I was learning from a postdoc, Spiros Michalakis, who actually stayed. He now has a different role at Caltech at IQIM. I learned a lot from him, and this strongly influenced the direction which I was going in. That's within IQI.
Within IQIM, I interacted quite a bit with Jeff Kimble. We did write some papers. There were also postdocs Darrick Chang and Liang Jiang who both actually came from the same group at Harvard as I did. We kept collaborating especially with Jeff Kimble. That was exciting.
ZIERLER: What was Kimble working on at that point?
GORSHKOV: There were a few things. He's always worked on atom photon interactions. It could be either individual atoms in cavities interacting with photons or ensembles of atoms interacting with photons. I think it was around that time that he started thinking about atoms near photonic crystals, where photonic crystals are structures in which you use materials to manipulate the properties of light. You create a material at a periodicity with wavelength comparable to the wavelength of light and the light near these materials has modified properties. He started thinking about that as well. I was part of these discussions. Oskar Painter was also part of these discussions. Oskar is still very much pursuing this. I believe actually Jeff as well.
ZIERLER: Your title, you were the Lee A. DuBridge Postdoctoral Fellow. That must've been some particular kind of honor given DuBridge was a president at Caltech.
GORSHKOV: There were several prize postdoctoral fellowships meaning that you were sort of a free agent. One was this, another Sherman Fairchild—something like this. They have additional ones now. There's an IQIM Postdoctoral Fellowship. I believe these people are also free agents although I'm not 100% sure. That was the thing that mattered. You're a free agent; you're not somebody's postdoc and they're not telling you what to do. You have freedom to come up with your own research directions and come up with your collaborators. This was the important thing. I guess the name maybe was nice too.
ZIERLER: The Presidential Early Career Award you got, recognized by Physics World, on manipulating individual light particles that strongly interact—was that work that you had done during your time at Caltech?
GORSHKOV: To some degree. The way this went is, back when I was in graduate school, some of the papers that I wrote towards the end—and I mentioned actually this research direction early on when we were talking—is how to make photons interact with each other. I wrote maybe one paper on that, still in graduate school. I continued thinking about this during my postdoc. Then I continued thinking about this after I started my position in Maryland. Throughout this, I collaborated with experimentalists. It was a combination of these things, I think, that resulted in the award.
ZIERLER: In what ways did this enhanced collaboration with the development of IQIM allow you to pursue topics or even ask questions maybe that simply were not even possible before?
GORSHKOV: I guess I partially answered that already. I was able to sit there and brainstorm with people like Jeff and Oskar on ideas related to ordered arrays of atoms or ordered arrays of atoms coupled to these photonic crystals. I was able to learn a lot of great stuff from the condensed matter theorists. In particular, Jason Alicea, I remember he taught me about some exotic topological phenomena. I since then have thought about these phenomena more, and that motivated some research directions that I pursued later when I started my own group. Things like this.
Maybe I can say more. When I was still at Harvard as a graduate student, I was not as connected to true quantum information theorists. I was doing more physics and less quantum computer science. The important thing at Caltech—and this is not about IQIM, it's more about IQI—is that this was actually a quantum information theory institute. This was the biggest change and the most exciting change for me that I would learn actually this field of quantum information theory that I had not been as involved in before. This was very important for me, and actually now it's becoming important for the entire field of quantum physics. Quantum information is now taking over. That's when it started for me.
ZIERLER: How parochial was your experience at Caltech? In other words, was there so much going on at Caltech that you were not necessarily following things that were happening at other centers? Or was really the research integrated at this point? You were keeping abreast of the literature.
GORSHKOV: It was integrated. I was definitely communicating across and collaborating with people all over the place, making use of ideas both locally and nonlocally. Definitely.
ZIERLER: How many conferences would you go to? How often were you publishing? Just to get a sense of your productivity during your Caltech years.
GORSHKOV: Conferences…I don't know…maybe three times a year. Productivity, I'll have to look it up. I don't know.
ZIERLER: Were there scheduled or weekly group meetings where everybody would get together and share ideas, tell everybody what they were up to?
GORSHKOV: There were weekly IQI meetings where people would briefly go around the room and tell what they were doing, and there would usually also be a longer presentation by somebody. That's just the quantum information theorists. When IQIM started, there were weekly IQIM talks which were also very important. Somebody internal at IQIM would talk about their work. Then afterwards people would mingle around and chat informally. Both of these were absolutely essential.
ZIERLER: At what point during the postdoc did you start to think about new opportunities, moving on from Caltech?
GORSHKOV: The postdoc is a very short time. It's two to three years. You start thinking about it pretty quickly unfortunately. You kind of have to. In fact, I think I even applied for jobs after a year and a half just to see how it goes, but then I stayed for the full three years.
ZIERLER: What was John Preskill's role overall? Was he a facilitator? Was he around to bounce ideas off? Was he hands on? Was he hands off? What was John's role in all of this?
GORSHKOV: Definitely hands off. I would say this about both my graduate adviser, Mikhail Lukin, and John. They're both hands off, and I think I learned this from them, and I try to do the same in my group. Definitely bouncing ideas around, listening to what people are working on and providing feedback. Also providing the environment.
ZIERLER: Were there any postdocs that you worked with that you collaborated with specifically more than others?
GORSHKOV: Yes. I mentioned there was a graduate student, Michael Beverland. There was a postdoc, Spiros Michalakis. There were my fellow postdocs Liang Jiang and Darrick Chang who came with a similar expertise. The three of us were the physicists, the systems guys in some sense, at IQI and then IQIM. These are some of the examples.
ZIERLER: Looking back, what would you say were your most significant contributions or discoveries or advances during your time at Caltech?
GORSHKOV: It's hard to place exactly when different things happened. The things that we discussed already—some of the contributions I made to the understanding of what you can do with polar molecules. That was exciting. Some of the advances on interacting photons that you already brought up. That was important and as you said it was recognized later. I think these are good examples. Some things happened towards the end that later blossomed into bigger research directions that I'm now pursuing.
ZIERLER: Yeah. What opportunities did you start to consider when it was time to think about moving on from Caltech?
GORSHKOV: You mean where to go?
ZIERLER: Yeah. Where to go, things to work on, who to work with.
GORSHKOV: Where to go was the crucial thing really. Right now, if you're a quantum information theorist, there are a lot of opportunities. Everybody is hiring quantum information theorists in academia, in industry. It's a great time right now to be a quantum information theorist. My friend Steve Flammia, who is actually now at Amazon, we were postdocs together—he used to say that quantum information theorists kind of fall through the cracks. That was the case back then because physicists think that we're not physics-ey enough and computer scientists think we're not computer science-ey enough, so nobody hires quantum information theorists. It was really true. Back in the day, Seth Lloyd, who is the superstar of quantum information theory, he had a hard time finding a job. He had to get hired by the mechanical engineering department at MIT. Mechanical engineering doesn't sound like quantum information theory. Basically to answer your question about opportunities—anything was good enough. The question was can I get anything? That was the outlook as far as opportunities go.
ZIERLER: Your current dual affiliation, that was there from the beginning between Maryland and NIST?
GORSHKOV: Yes, that's how it was set up. The thing I was very excited about was the JQI, Joint Quantum Institute. The reason I was excited about it we discussed already. It's kind of like IQIM in the sense that it brings a lot of people together. That's what I wanted to be part of and that's a joint institute between the university and NIST.
ZIERLER: What was the job that you applied to? Was it a federal job with NIST knowing that you would be geographically in Maryland, or was there a posting at UMD and you went through NIST to get the job?
GORSHKOV: It was NIST. Well, it was kind of like a dual effort. I learned that there was this possibility of getting a NIST job. I learned this from Carl Williams who until very recently had the top quantum leadership role at NIST. He actually just retired. He was the hiring person at NIST, but he was also part of the JQI. He helped mediate this conversation and I got the understanding that not only NIST was interested in hiring me—because that was important—but also JQI was interested in making me part of their center. Two hurdles needed to be overcome. JQI voted to make me a fellow of JQI. Then Carl made sure that I got hired at NIST.
ZIERLER: Were you on the job market more generally? Did this come to you when you were not considering other offers?
GORSHKOV: I was on the market more generally. I was applying all over the place because you just never know, especially back then. You never know even now. The job market is just so stressful. I encounter this always now with postdocs for whom I'm writing recommendation letters. Very, very stressful. Actually something is happening right now: one of my postdocs is in an emergency mode where he has to decide by tomorrow what to do. So, yeah, stressful.
ZIERLER: This must've been the ideal opportunity for you given all of the possibilities—NIST, Maryland, the Joint Quantum Institute. It must've been perfect!
GORSHKOV: Absolutely. There were some other things that I was considering before, but when this opportunity came, I was extremely excited. Yes. It was perfect. You are right. Exactly.
ZIERLER: What did you take with you from Caltech? What had you learned? Who had you interacted with? What were the ideas that you developed that you really took with you that might not have been possible otherwise?
GORSHKOV: First of all, the bigger picture of thinking about physics using ideas from computer science, from quantum information. This thing was really important, and it's been expanding and expanding in my research. Something that I learned from Caltech postdoc, Spiros Michalakis's work: mathematical tools for calculating how quickly quantum information can move through a quantum system called Lieb-Robinson bounds. Spiros taught me that stuff and this has been very important since. I wrote some papers with Spiros afterwards, then some without, and my group is still pursuing that.
The stuff that I mentioned with Jason Alicea. He taught me some stuff relating to topological phenomena in condensed matter systems, also with relevance to quantum information. I've pursued some of that as well. The stuff with Jeff Kimble and Oskar Painter and Liang Jiang and Darrick Chang on photonic crystals. This also was important. A lot of things. Yes.
ZIERLER: Alexey, for the last part of our talk we've already brought it right up to the present. Looking to the future, with all of the caveats about how difficult it will be to predict the future where do you see things headed? What are the most exciting developments in the future? Where do you fit into that? What has Caltech given you to be a part of these advances that are coming?
GORSHKOV: That's a lot of questions in one.
GORSHKOV: [laugh] First of all, it's a very, very exciting time to do what we're doing. We don't have to really beg for resources at this point to do what we're doing. Many people feel that there are almost too many resources. That's exciting. We don't have to prove that we're relevant. People know that quantum scientists are relevant. That's exciting. As a result, of course, all of these experiments are being built up, these controllable, large, pure quantum systems that will lead to exciting technologies. It could be quantum computing, but there are other things. Quantum networking, quantum sensing, etc. It could also just help us learn some exciting physics, just understand some fundamental stuff that's maybe not technologically relevant, but just exciting. This was always the case, but now there are especially many opportunities for doing this. Certainly, that's what I want to think about. That's what my group is thinking about. Everything—the technology and the exciting physics insights that can be obtained.
As far as what Caltech gave me…as I mentioned in the beginning of our discussion, I started here in Maryland at the interface of atomic molecular optical physics, condensed matter, and quantum information. I'm still at that interface, but quantum information is becoming more and more important out of these three. What Caltech gave me is really this quantum information part.
ZIERLER: Alexey, this sea change that you've alluded to where there's more resources now than there certainly were five, six, seven years ago—what accounts for that? Who's making those decisions? What are some of the advances in the field that explain this additional interest, these additional resources, into quantum computing and associated work?
GORSHKOV: The thing that is important to researchers is the funding that comes from the federal government—the Department of Energy, the Department of Defense, NSF. One thing that happened is they just offer now much more of this quantum funding. Now why this happened is people saw opportunities in quantum and that's why they are giving the funding, but people also started getting worried that maybe our competitors in Russia or China are funded better. We might fall behind and this might be a problem. A combination of these things. People on the Hill passing legislation, including the famous National Quantum Initiative, is a result of seeing opportunities, being worried about competitors, and other developments. So at the end there is much more quantum funding. That's one aspect of it.
The other aspect is the quantum money in industry. Federal funding and industry of course feed onto each other and they're motivated by similar things—opportunities and the fact that people are now afraid. Some bank says, "What if all the communication that I'm using right now—once people build a quantum computer they'll be able to decode all of the secret messages that I send. I should be thinking about what quantum can do for me and what quantum can do to me."
GORSHKOV: Everybody's putting in a lot of money—and of course, venture capitalists are like "Ooh. This looks like where I can get something exciting going. I can earn some money." So quantum resources are coming from multiple directions. It's great.
ZIERLER: Alexey, finally last question for you. Because right now you're in building mode yourself—you're building up your own group hiring postdocs, graduate students, lots of exciting things are happening for you. To what extent did your experience at IQI, IQIM serve as a model or a game plan for what you want to accomplish to push the field forward as you see fit?
GORSHKOV: I'm not in a growing mode anymore. I'm more in my steady state or maybe even I should dial down a little bit as far as the size of the group goes. As far as what I learned, a couple things. One thing we already discussed—how to manage the group. A more laid back approach of Mikhail Lukin and John Preskill I definitely appreciate and just giving people the freedom. Just make sure that they're saturated with exciting ideas and that they talk a lot to each other to do the best science. Something else actually that I learned at IQIM is I mentioned these IQIM seminars where there'd be an internal talk and then people would chat afterwards with free food. I really wanted to bring this to JQI—they didn't have that—to the University of Maryland. I established a seminar. I mentioned IonQ gave money for that. I mentioned that earlier. I established a seminar where an internal speaker—student or postdoc—gives a quantum talk and there's free food either before or after, pizza. I thought this was crucial, so I brought that in. Maybe you're also asking scientifically?
GORSHKOV: We discussed that. It's very important for this quantum research to be integrated across condensed matter, AMO, quantum information on the one hand and across theory and experiment on the other hand. That's what IQIM did. That's what Center for Ultracold Atoms at Harvard and MIT did. That's what we're doing here. I think this is crucial and also fun.
ZIERLER: Well, Alexey, it's been so fun talking with you. It's been great getting your perspective as we're building this history of what IQI/IQIM represents. I'm so happy we were able to do this, so thank you so much.
GORSHKOV: Thank you, David. It was fun.