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Welcome. Today uh I'm very excited for this all-in interview with this week's
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Nobel laureate, winner of the Nobel Prize in physics in 2025, John Martinez.
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John, welcome to the all-in interview. Yeah, thanks for inviting me. Um I'm quite excited about this uh this talk
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and uh you know, love to explain to people about you know, what this prize is all about.
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All right, besties. I think that was another epic discussion. People love the interviews. I could hear him talk for
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hours. Absolutely. Oh, he crushed your questions in a minute. We are giving people ground truth data to underwrite your own opinion. What did
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you guys think? That was fun. That was great. [Music]
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Well, the Nobel Prize is the most prestigious honor and particularly in physics that I think can be awarded.
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You're in the record books. It's going to be an incredible ceremony coming up for you. Maybe we could go back to the
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beginning in your history. I'd love to hear a little bit about, you know, where did you grow up and how did you get started with your interest in physics?
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Uh, well, so I uh I grew up in San Pedro, California, and uh, you know,
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grew up there my whole time. My my father was a fireman and my mom stayed
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at home, took care of us, and um, you know, through the years I was always
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interested in science, technology. I'm going to say one of the things is, you know, my my dad, you know, actually
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didn't have a high school education, but very smart person. He was always building things in the garage, various
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projects. So, I grew up kind of knowing how to build things, which also kind of tells you how things work, you know,
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kind of empirical view, you know, tactical view of how physics works. So
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uh when I took physics in high school, I actually loved it because there was actually some math behind it and
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concepts and you know really made sense to me and uh you know I I just really
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you know fell in love with the subject and then went to UC Berkeley and and did pretty well there and enjoyed it. Uh
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enjoyed it a lot. And then in my senior year at UC Berkeley I had a class from
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John Clark who was my adviser and found out what he was doing. and he was just
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starting to look at these quantum mechanics and electrical devices stuff
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and it sounded really interesting for me. I guess I have, you know, I guess I
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could see maybe when something maybe would would take off. So I started to to uh to to do the graduate school work
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with him. You went to Berkeley for graduate school. I went to Gertie for graduate school, which you're not supposed to do.
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I was originally a physics and math undergrad at Cal. Okay. I changed my major later and
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actually got my degree in astrophysics. There was some upper division math class that really turned me off to math as a
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major. There was just so many proofs. It drove me nuts. Right. Right. And then physics was always exciting,
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but I liked uh working in the astro lab and I worked actually at Lawrence Berkeley Lab.
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Oh, okay. Yeah. But then you you stayed at Berkeley and went to grad school, right? Yeah, I stayed at Berkeley, went to grad school. We started this project a couple
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years into grad school. I forget exact date. And what was interesting is this
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was a question that was actually posed by professor Anthony Leget who won the
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Nobel Prize for you know helium 3 you know physics uh in I think 20 2003
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was that super fluid super fluid helium 3. Yeah that's right. So he showed like if you put helium 3
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cold enough it kind of almost has this new sort of characteristic with the physics and how it moves and how it
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works. Well, it has a this super fluid behavior, but it has a very complicated
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behavior because of the more complicated nuclei of the helium 3. And
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this had been discovered and people worked for a while to figure that out. And he, you know, helped develop the
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theory for that. So, he was quite wellknown, very, very smart person. And
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although he won the Nobel Prize for that, okay, there's not much helium 3
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physics going on, but for the question that led to our experiment, okay,
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there's a huge field. And the question was, do macroscopic
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objects behave quantum mechanically? Okay, and this is a macroscopic object
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might be a small ball. In our case, it's an electrical circuit with billions of electrons in it, billions of atom and is
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the collective motion of say the ball uh quantum mechanical. Now, you know, if
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you think about throwing throwing a ball against the wall, it's going to bounce off. But if you make the wall thin
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enough and the ball light enough, it'll then every once in a while tunnel through because of the, you know, laws
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of quantum mechanics. So, um hold on, let's just pause on that for a second. And I think that's really worth
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spending a moment on. Yeah. Great. So when we talk about quantum mechanics,
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when we talk about the relative position or energy or movement of a particle at
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the atomic scale as small as an atom or smaller than an atom, we have to use
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kind of probabilities to describe where things are going to be. That was what was really kind of the big understanding
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of quantum mechanics in the early 20th century, right? is that there's the probability of things being where
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they are and moving as they're moving there. It's not like like deterministic like we can see with the ball that we
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throw around. When you get very very small things get very fuzzy and it's very hard.
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So you hit upon upon the key idea here maybe by accident but it's very
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important. Quantum mechanics was developed for the theory of small
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things. You know, electrons, atoms, you know, things things that are that are
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the the fundamental constituents of it, but very small. And um you know, if you
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take an atom, it's made from electron and a nucleus. You know, classically, they attract each other and they would
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just, you know, combine together and then atoms basically would have no size.
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Why do atoms have size? Okay, that you know that that was one of the the
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strange things and it's because this atom is kind of not a a point particle.
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I used to say to my kids that the electrons were fuzzy. Okay. And and quantum mechanically it has some wave
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function and extended. You can think of the electrons being all around the nucleus at the same time. So um it it's
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just a very strange behavior u but of small things uh and of course very
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important as how atoms work and how we describe nature. So quantum mechanics
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ultimately became a field that people say is very non-intuitive in terms of
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understanding where small small particles are, the energy they have, where they're moving to and and
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basically we resolved to figuring out that we had to use these functions. It's
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not just a single point, but it's a distribution. It's a whole bunch of places and there's a probability of
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where the atom could be or where the electron could be. It's also a probability of how fast it might be moving. All of these things become
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probability functions. And you develop a mathematical theory for doing this that you know takes you
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until your third year in university to really know enough math to understand that. But basically that's right
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these are forming waves waves of the electron. So you have kind of a wave and
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electron around the nucleus describing what the uh the electrons are. And these
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are kind of like standing waves, you know, it's like hitting a string. Uh, you know, if if different length
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strings, different tension strings form different notes, these vibrations of the electrons around the atom can vibrate at
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different frequencies. So rather than think about an electron moving around an atom in a predescribed
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path and I can know where it is at any point in time, the right way to think about an electron around an atom is it's
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in a wave. It's a and it's it's a long there's a wave that describes kind of where it is and it's doing
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and you have the electron and you have the proton attracting it. So the whole wave theory
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combines all those two and you know gives you a description of how the the atom works and quite accurate
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description too. And so one of the other kind of features that arises from the fact that everything at a micro scale is
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described by wave functions is that there's a small probability of something kind of extreme or extraordinary
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happening. Like the one example is Stephen Hawking figured out that you
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could have a particle and antiparticle come out of nowhere in the middle of space and the antiarticle goes into the
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black hole. The particle shoots off. Yeah. And that the probability of that happening is so low, but it happens
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enough that the antiparticle actually starts to delete part of a black hole. And that's how black holes evaporate and
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this theory all these interesting things. But can you tell us how what quantum tunneling is? So this is another one of
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these sort of features of quantum mechanics that arises from the fact that these things are kind of waves and
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probability functions. Yeah. So if if you have um if you have an electron just traveling through space
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hitting hitting a wall let's say there's a little wave wave packet wave function
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to it. So it's not a single particle. It has some extent to it. And what happens
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is that when that particle hits the wall, quantum mechanics say there is some
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amount small amount of this wave function or if you like the particle going through the wall and then to the
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other side. Now most of the time it uh it bounces off but every once in a while it goes
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through. And you know this is seen in um uh everyday devices. This is not and as
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if you build very small um memory circuit you have to worry about
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electrons tunneling and charge leaking off your capacitor. Uh they have
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magnetic memories that depend on these tunnel junctions. So this is a very well-known phenomenon and if you make
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the this barrier this insulator just you know 10 20 atoms thick then that's thin
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enough for it to go through to go through. So this is what's so interesting. Um you can actually predict
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the number of electrons that might tunnel through one of these barriers one
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of these insulating barriers as they're called over to the other side which really is crazy to think about. It's
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just like walking through walls, right? I mean, yeah, that's that's the idea. Yeah. So, going back to the story you
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were sharing, you're in grad school, right? And then Leot proposes this idea. Maybe you can share a little bit more now that
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we've got I think a bit of the basics on what was discussed, which was zooming out a bit like rather than just
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think about all of this happening at a microscopic scale, is it possible for it to happen at a bigger scale?
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Yeah. And again we've been talking about quantum mechanics is the physics nature
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at this microscopic atomic scale but the question was if you made a macroscopic
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object would it obey quantum mechanics also okay and then you know that was the
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basic question and it turns out that there's a very natural system to look at
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looking at an electrical system and look seeing for quantum mechanics an
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electrical system where the currents and voltages of essentially electrical
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oscillator does it behave like a classical physics or does it behave with
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this quantum mechanical nature to it? And that was the question. Now it turns out that when you think about quantum
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mechanics and thinking about well there's the quantum behavior but then at some point you have to measure it which
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then turns it into a probability. There's something called the Schroinger pat cat paradox where um in the paradox
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you have your radioactive decay and then you you you
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let it happen for let's say half of the radioactive decay time and then you say
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and then the in you have a ready detected decay a detector and then a bottle of cyanide which will kill a cat
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and then do you say you know after some amount of time is the cat in the dead in
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the live state. Okay. And you know, physicists, you know, and this is this
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good question. Einstein brought brought it up or Shoner brought it up. A lot of people uh discussed it. Uh but Alleged
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pointed out that the reason this is a paradox is you can believe that a
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macroscopic object like a cat could be in a quantum superposition state. And in
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fact, there was no experime experimental evidence that this could happen. And
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that was his point. So um so he said well you know people should be testing this and let's see if it's true and uh
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as a as a young graduate student who just you know learned about quantum mechanics and it's like oh that's a
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really great great question that's something that we should try to do and we should try to do an experiment you
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know on on the suggested system uh to look for quantum mechanics. And the the
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original proposal was looking for the tunneling. Well, it turned out to be more than that, but uh the it look for
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tunneling. Let me just kind of describe another way is you know the macroscopic system could
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be my entire body. Could I walk through a wall? That's right. And then the probability
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of all of my atoms being in the perfect moment, perfect position, you know, to
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to be able to kind of cross through the wall is so low, it would never happen in this or many other universes of
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and and that's the problem is that most macroscopic objects when you try to think about the quantum mechanics that
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won't happen. Okay. So, right. There's a small probability one electron can cross over a barrier,
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but the probability that many cross over at once is lower and lower and lower and that makes it very difficult to see at
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scale. And what what happens is if you look at an electrical circuit then the
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parameters become favorable for seeing this kind of macroscopic behavior. And
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okay, it's hard to go into the the whole physics of all that, but it's basically
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because you can make a circuit that operates at microwave frequencies. So
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instead of you trying to go through the wall once a second, it tries to go through the wall five billion times a
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second. Okay. So then it's it's a lot, you know, more you know, you have more chances to go through. And uh uh the
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other thing is the just the various parameters that involved in quantum mechanics you know are favorable for
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seeing this kind of phenomena. You have to do the experiment right but uh it's favorable for doing that.
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So one of the parts of your experiment you created what's called a Josephson
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junction. Is that is that correct? So this is two superconductors with a barrier between them. Right. I got
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really fascinated by superconductors when I was maybe 12 years old. I I went and bought a superc conducting disc etum
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berium copper oxide. Yes, that's right. From the back of Popular Science and then I went to UCLA and I got a a jug of
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liquid nitrogen and then I floated a magnet above the disc because of the Meisner effect and I had
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it at the science fair and I and I did very well with the science fair that year because I showed this really What year was that? Was that when it was
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discovered? Must have been 919. Okay. Yeah, that was close enough that that was good. Yeah, the hard part is
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getting the liquid nitrogen. But yeah, and I had a friend whose dad was like a doctor at UCLA or something like
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that, so he was able to get the liquid nitrogen for our demonstration. Right. Yeah, that that was the hard part. Okay.
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I've always been fascinated by the physics of superconductors and maybe you can just explain one of these important
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features of the of superconductors as it relates to kind of resistance and current flow and then we can talk about
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your experiment. So, so what happens is um when a a
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material goes superconducting all the electrons condense into one
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state. Okay. Now to just to give you analogy of how it's not perfect analogy
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it's close analogy. If you have a normal metal any metal we have at room temperature it's like a gas of
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electrons. It's like you know gas in the air. And then when you get below the
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superconducting temperature. Sorry, I think we should just explain that. So, so you have a metal all the
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electrons are kind of moving around. They're they're perturbed. They're all different energies, different states.
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That's right. Different energies, different states. You know, there's some firm statistics. Not go into that, but
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it's more or less looks like a gas. You think of a of a gas and then when you cool it below you know a certain
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temperature it then coaleses into let's say a solid like like atoms will and the
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electrons coales into the something cooper cooper pair bcs condenset is the
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name where all the electrons are kind of locked together and doing the same
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thing. Now the nice thing about that it's not like they're frozen in place
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but they have a free parameter that allows them all the currents all the electrons to flow in some direction
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which is the supercurren in a superconductor meaning a material that's cool enough that it reaches its
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superconducting critical temperature. Right? So suddenly all the electrons can still move. They can still create a
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current, but but they're they're moving together like they're in like in my analogy like
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they're in a solid instead of the gas. And because they're moving together,
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okay, then then when you work through all the physics, they are not um you
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know, they aren't randomly scattering off things. They're just moving together. And then you get a supercurren
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where for example if you made a ring a superconductor superconductor that current would basically flow for forever
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around the ring. This is what you saw with the floating magnet. Right. That's so interesting. I've
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always uh thought and there's obviously been companies started around the idea of creating an infinite battery where
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you could store technically forever electricity because the electrons are just moving around. If it's
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superconducting it can they can just spin forever around that circuit. And people actually do use big
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superconducting magnets to store energy. And when you get an MRI that you're in a
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you're in a liquid helium machine with a a superconducting magnet, they charge it
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up and that magnetic field is basically there forever. Uh you know, waiting for
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people to to go inside it. It it's kind of strange to be in you're inside this
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super cold magnet there. But they've designed it very well. Works well. So this Josephson junction is two
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superconductors. They're on either side of a barrier that you create, an insulating barrier. And then maybe just
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explain the experiment and and what you guys measured. And this this was all while you were in
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grad school, right? Yeah. Yeah. And and uh and this is this Jose junction because the Cooper pairs
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have to tunnel through it, but they kind of tunnel through it together without any loss. This this actually forms
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what's called an electrical inductor in circuit in circuits. So an inductor is
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normally a a coil of wire that stores energy and its magnetic field. Here this
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this just stores energy of the electrons tunneling through here. And so it's a it's something called we call a kinetic
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inductance and it happens with this but that forms a nonlinear inductance and
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with a capacitor in the circuit that forms an inductor capacitance resonance
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circuit which is in your old which is like in your radios you have filters of
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LC resonance circuits to filter your signal and do anything. So this is a very common microwave and uh you know
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radio frequency uh element that you use all the time to make electrical
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circuits. So I just want to simplify that you have these two superconductors split by this barrier. There's some tunneling some of
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these electrons are actually going through the barrier to the other side and then you can effectively measure all
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of these different changes as you change the temperature. You guys were putting different voltage states into this
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circuit that you built. And what you saw and what you measured and what you demonstrated was that there were these
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very kind of discrete or specific changes that happened that basically
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demonstrated quantum mechanics at scale. That's right. So, so this inductor
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capacitor resonator which you just treat as a you is a charge and a current going
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through but because it's quantum mechanics there's this wave function to it. So there's some uncertainty in these
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and then given just the way that the simple electrical circuit works um uh
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you can then demonstrate the quantum mechanics one of the tunneling which is a little bit hard to describe here but
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you can see tunneling but I think the little bit easier thing maybe easier is
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to look at the energy levels of this and let me kind of explain that when people
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discovered you know atomic physics and started doing any doing this they um
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excited a gas of of you know some gas and the light coming out of that gas
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would be at certain colors of frequency. So if you go outside and you have the sodium lamps on, these are kind of the
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yellow lamps, you have, you know, kind of a single frequency coming out of that lamp. Or nowadays you look at LEDs,
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there are certain frequencies that come out of that. And this is a quantum
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mechanical effect that the how the electrons travel around the atom.
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There's only certain kind of frequencies that they oscillate at. Now,
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classically, you would expect there to be all different frequencies that it spirals around or spirals into the
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nucleus. So, that's what you expect. But we saw these discrete frequencies.
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And so, by measuring those discrete frequencies, you now had proof that there was quantum mechanics
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happening at a macro scale. That That's right. And you published this work. And was
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there a lot of attention when you published this work? This was in 1985 86.
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Yeah. 85 or I actually forget but 85 or 86. And so was there much attention on this
00:23:23
work at the time? 8. Yeah. This was a big question and people wanted to you
00:23:28
know understand that and you know we published it in physical review letters and it got a lot of attention and I
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think we had a little article in Scientific American that was very proud of
00:23:41
that wrote about that and uh yeah it it was you know it was kind of a kind of a
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big deal. What did you go on to do at that point? Was it considered groundbreaking Nobel Prize-winning work and what was the
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story at that time when this came out? Yeah. So, you know, it was an it was an
00:24:00
important piece of work and people noticed it, but you know, it it you
00:24:06
know, we we showed that quantum mechanics worked and quantum mechanics worked on the macro scale, which was
00:24:11
nice, but one could still, you know, argue, well, what is it good for? What are you going to do? And the in fact the
00:24:19
secret of an important scientific breakthrough is does it lead to other experiments and
00:24:26
other papers and other inventions and the like and uh that kind of took uh you
00:24:32
know many decades to happen because it was so new and people had to do do that.
00:24:38
So I would say it was noteworthy at the time but you know not necessarily you
00:24:43
know something for a Nobel Prize because it was just kind of you know weird and went off and you know what are you going
00:24:50
to do with it? But what happened at the time was very interesting and at the end of my thesis
00:24:58
time there was a conference in uh UC Santa Barbara where I came here for the
00:25:04
first time. Yeah. and uh they they were talking about this experiment but the very last
00:25:10
day the last talk was by Richard Feman very well-known physicist
00:25:16
of course the greatest yeah the great yeah right you know I kind of idolized him and and read his his his
00:25:24
books and whatever and he was talking about using quantum mechanics for computation which is
00:25:32
building a quantum computer so he gave a talk that was, you know,
00:25:37
really kind of amazing. I'm going to be honest as a student. I I didn't quite catch everything and my Michelle dev my
00:25:45
dear friend said yeah maybe some of the things wasn't quite figured out at the time but afterwards he was absolutely
00:25:54
mobbed by people asking him questions cuz it's so interesting to think about
00:25:59
taking this this you know basic law and actually doing computation with it
00:26:04
right and I was a graduate student so I was kind of at the outside ring you know you
00:26:10
have the professor professors in close and whatever and I was just a lowly graduate student so I could hear a
00:26:16
little bit but what I what I learned from this it was a great question and
00:26:21
and something that would be kind of worth doing you know for your your life pro your life work because it's so deep
00:26:29
and so interesting and maybe practical and the like so that really motivated me
00:26:35
yeah so that big idea is to use quantum mechanics and these properties of
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quantum mechanics to do computing. Yeah, that's right. And and I would say
00:26:47
uh uh soon after that other people in the field got a little bit more specific
00:26:52
and showed how you would how you would do it. And then it was in the early 1990s, maybe 5 years later, that Peter
00:27:01
Shaw came up with this factoring algorithm to to solve a you know, a real world problem with it.
00:27:07
Yeah. And it took a while to people figure out. It was very abstract and you know people quite weren't sure what to
00:27:13
do. But but like I said I could see that in all the the crowd around Fineman
00:27:18
asking them questions that this was the most you know most interesting
00:27:23
fundamental question you know how to combine quantum mechanics with doing computation. It's it's really amazing.
00:27:31
And so you started to do that with your life's work pretty much. you go on to a
00:27:37
very good career. Yeah. So my career path um was of course
00:27:42
quantum computing was getting developed and and it took me a while to really get
00:27:48
go all in on it. Okay. Yeah. So um what happened is Michelle Devare was was from France from CA
00:27:56
France went to Berkeley went back I went there as a posttock and worked with them
00:28:02
and they were young and unknown at the time and people like well you're going to go to Europe and you're not going to
00:28:08
get connected to US science but I knew Michelle and Danielle Eststev and
00:28:13
Christian Abino the people I working with were absolutely brilliant okay and
00:28:18
they've had a very illustrious a career. So I went over there because I knew that
00:28:23
was great. And we continued to do experiments on this. Yeah. And then after that I came back to the
00:28:29
US and I worked for the National Institute of Standards and Technology.
00:28:34
And it turns out just down the hall from Dave Wland and his group who went a Nobel Prize for atomic physics for you
00:28:42
know doing quantum computation. And I worked on some with doing experiments on counting electrons and working for
00:28:49
metrology and then did other experiments. And then in late uh the '9s
00:28:56
I I just again went all in on building a quantum computer. There was funding available at that time. It had
00:29:03
progressed enough theoretically that the US government started you know funding
00:29:08
this to see if people can do it. And so then couple years after 2014 I think you
00:29:16
ended up at at Google's quantum lab in Santa Barbara. Is that right? I was at UCSB for um 10 years or so
00:29:23
which was wonderful and built up the lab to go from very basic things to building
00:29:28
a five and then 9 cubit quantum computer. And then during that time, Google got interested and I I kind of
00:29:36
decided that although academia was great, it would be hard to get the team
00:29:42
together and keep them together for a long time to build this complicated machine and Google had the money. Okay.
00:29:49
Yeah. So, so we went there and we started off fairly small uh mostly from
00:29:54
people coming from my UCSB group and then in uh 2019
00:30:00
we published this quantum supremacy experiment with 53 cubits where we made
00:30:07
a lot of cubits and we made them really good and you know fast and whatever so
00:30:13
that we could run some algorithm a mathematical algorithm that um what it
00:30:21
produced some output uh that was took you know much much longer on a classical
00:30:27
computer to to emulate and do that. It was not practical but it was a
00:30:32
demonstration of the power of a quantum computer that it worked. Well, just maybe give
00:30:38
your description of a cubit and maybe we can relate, you know, how do we build
00:30:44
these quantum computers from cubits to the Josephson junction and some of the early work you had done that you ended
00:30:50
up winning the prize for. So very simply, we have a metal wire and
00:30:56
a metal wire that gets put together on this Joseen junction which represents a
00:31:02
a an inductor flowing through here. And then from this wire to this wire, we have a capacitor.
00:31:09
And then we set that up to oscillate at about 5 GHz cell phone frequencies.
00:31:16
Uh uh you know to to form the cubit. Okay, this oscillating thing. And then
00:31:22
there's at low temperatures superconductors you know all this magic we can we can get quantum mechanical
00:31:29
behavior out of that and then you can measure that quantum mechanical behavior create a
00:31:34
representation and use that to run your computing. That's right. What you can do is you put on microwave pulses to change the state
00:31:42
of the quantum computer, change the way it oscillates and then we connect it to
00:31:49
um it's a complicated readout circuitry uh to you know in the end figure out
00:31:54
what state it's in. Okay. And then and then you you connect
00:32:00
just an array of these and you just use capacitive coupling from you know one
00:32:05
one wire to the to the next one to to couple them together and it's more
00:32:10
complicated than that but that gives you a good idea and then just to understand
00:32:16
your work that you won this Nobel Prize for that demonstrated this quantum
00:32:22
mechanical phenomena at scale. Is that part of the design of a cubit and the
00:32:28
circuitry? Did that inform that design work or explain it rather? Yeah. Yeah. It was the very basic simplest
00:32:35
circuit. uh you know we were using analog simulators at the time not even
00:32:41
the I took data with a computer but this is this is far back enough that you know
00:32:46
it was very rudimentary and then over the years we just got more sophisticated design by the whole field
00:32:54
you know many many people and uh and we were able to put things together in a way to actually build a
00:33:01
computer now right the the I would say the reason why It's interesting from the Nobel Prize thing
00:33:09
is what it led to and what it led to right now is a thousand maybe several
00:33:16
thousand people around the world doing research to build this superconducting
00:33:22
quantum computer and and it's just turned into enormous field large number of papers large number of people people
00:33:30
selling quantum computers IBM is selling quantum computers people are selling time in the quantum computers and the
00:33:37
fact that it was a it was a useful idea okay that led and and and brought into
00:33:43
form uh uh all all these different experiments ideas and many many people
00:33:48
contributed this I mean it's very interesting and I think just this broad question or observation
00:33:55
that sometimes inquisitive minds
00:34:01
leads to research that leads to some set of discovery that are completely not
00:34:06
apparent until 40 years later. the effect or the impact it may have had on building an industrial field like
00:34:12
there's now quantum computing everyone feels is on the brink of actually achieving what people have
00:34:19
talked about in theory for decades but seems to be getting very close to doing it and yeah I I can talk on that but I would
00:34:25
say um you know this field many other
00:34:30
ideas on how to build a quantum computer has been generated and uh it is very
00:34:36
exciting field quite large field and I would say that the science was very very
00:34:42
deep too. To get these things to work you have to invent lots of different devices. You have to think about
00:34:49
materials. You have to fabricate it, build complex control systems.
00:34:54
Engineering and physics is is to me quite beautiful. And and just to tell
00:34:59
you a little bit about me, um you know, I grew up building things and as an experimentalist,
00:35:05
you know, I like to to build instruments, you know, build experiments to show this. And this was kind of the
00:35:11
ideal project for me because, you know, from very early on it was like, well,
00:35:17
let's, you know, do this great physics, but let's also build something. And by saying, well, what do we have to do to
00:35:24
build a quantum computer? that kind of led me to know what physics we have to test and what are the kinds of things we
00:35:31
have to build and that's just the way my mind works. I'm I'm much more practically oriented. So it was a
00:35:37
perfect field for me to get in and that's kind of what you know intuitively led me to you know want to do this in
00:35:43
graduate school. And I think it's just so fascinating the amount of engineering
00:35:48
and technology you have to do to make this work. Where are we in quantum computing
00:35:54
evolution today? So what's the state? At what point will we have call it
00:35:59
generally accessible and generally useful quantum computers that can do all of the amazing things everyone's kind of
00:36:06
talked about for decades that one would be able to do quantum computers. That's right. So um right now we're
00:36:13
we're about 50 or 100 cubits for the superconducting case but they they can
00:36:19
be fully controlled and run real algorithms and do very complicated things. They have a lot of other systems
00:36:26
that can do that. I think the the newcomer on the block which looks good is neutral atoms where they've made big
00:36:33
neutral atom systems but they they're still working to get the gates
00:36:38
controlled really well and the like. But what's happened right now is we can run
00:36:44
genuine algorithms on that and people have uh h you know have ideas they want
00:36:50
to run but because these cubits are not perfect okay you it's an analog control
00:36:57
system and fundamentally these quantum bits have a little bit of error to it
00:37:03
little bit of noise to it you can only run so complicated of a project and it's
00:37:09
good enough to write scientific papers and try things out. Uh, every once in a
00:37:14
while people say they've done something uh, you know, that's hard to compute and
00:37:20
well that's fine, but they aren't really big enough to be useful yet. They have
00:37:25
to get bigger and they have to get better, less noise. Do you have a point of view on the timelines? This is everyone's
00:37:32
speculation and there's been more hype than reality. Yeah, there's more hype than reality and and uh, and it's hard. I used to not
00:37:39
want to speculate that but since I started a company then I can do that and
00:37:45
what we want to do and it's a timeline of many other groups is to do something
00:37:51
in let's say in the next 8 10 years something like that but the problem is you know people are predicting 10 years
00:37:58
you know for a while now so okay we we have to do that but um I can tell you
00:38:04
for what we're doing is that we've identified by what are kind of the
00:38:10
technology bottlenecks of the current fabric turn ways to make a a quantum
00:38:16
computer. We've written some papers on it and you know we're working with people in the semiconductor industry to
00:38:24
manufacture this in a much more coste effective quality way you know the way
00:38:29
you make these GPUs or something and we think uh you know when we get that to
00:38:35
work we can scale up very rapidly so in in a let's say 10year time scale
00:38:40
something like that in a lot of technically difficult fields like fusion energy perhaps even quantum
00:38:48
computing. They are seeing profound acceleration in getting to their crazy big goals on
00:38:54
these very big technical projects because of AI. Is AI starting to play a role in solving some of the engineering,
00:39:02
material science, scaling, noise issues that we've seen historically in quantum
00:39:07
computing? And do you think that there's an acceleration underway in performance improvements because of AI? there there
00:39:13
may be um my partic and and and there's things we can maybe do modeling and the
00:39:19
like. We also think what we can do is use the quantum computer and AI together
00:39:26
to solve the problems better. So that that that's what our theory team is proposing. I used to work with Google
00:39:34
quantum AI. That's what they're proposing. So there's a general feeling of that. My particular view though is
00:39:41
that in terms of this control, if you don't build your system cleanly enough
00:39:48
and you know that the control is clear enough, uh you're you're not going to
00:39:53
get the the great performance out of it. So I'm a little bit old school here and
00:39:58
and working on you know building it that way. There's certainly some elements where you can use AI,
00:40:05
you know, in the decoding circuit for the the error correction and the like. But the one thing to mention to you is
00:40:12
that, you know, these cubits are are naturally very noisy and you can maybe
00:40:18
do sometimes 100 for bad cubits and maybe a thousand maybe few thousand
00:40:25
operations before they kind of lose their memory. You know, you can think of it as like dynamic RAM where you have to
00:40:32
refresh it. Well, you have to refresh it with error correction. And because of that, you're talking about a million
00:40:38
cubit quantum computers to be general purpose and solve really hard problems.
00:40:43
There might be some a million something. A million is a good round number for it. Maybe a little bit
00:40:49
more. And right now we're at you know a hundred or you know a little bit more than that. So we have a ways to go.
00:40:56
What is your view on China and the progress that they're making in this technology versus the US? This is the
00:41:03
topic dour in every field, industrial field, computing, science is where's
00:41:09
China at compared to the US, the comparisons and everyone's worried about the progress in China versus the US and
00:41:15
what that means. So I can talk about my own field but when I have read the
00:41:22
papers that um duplicated what we did at at Google on the quantum supremacy
00:41:28
experiment you know they know what they're doing. I mean they they go through the theory they talk about a lot
00:41:34
of it is very similar to what we're doing but they know what they're doing and they're getting great results. And
00:41:41
the thing that scares me a little bit is, you know, last December the Google
00:41:47
group published the latest results, which is really much nicer. They made some real improvement, but then China
00:41:54
soon afterward published something kind of indicating they were, you know, on
00:41:59
par or near par or something to it. And, you know, I'm worried that the the
00:42:05
Chinese government is saying, well, you can't publish anything until it's in the Western press. and then you can, you
00:42:11
know, then it's open and you can talk about it. That's precisely what I've heard. And so, yeah. So, so uh, you know, I I'm I'm a
00:42:18
I'm a little bit uh concerned about that. Now, what we're doing with our our
00:42:25
company is we're doing a new generation of fabrication of the devices. And I
00:42:32
would cons consider in my my my research we had the simple fabrication with the
00:42:38
original papers in 85 and then around 2000 we had more sophisticated
00:42:43
fabrication and then for the quantum supremacy experiment we did something
00:42:48
even more complicated other groups too but we want to do a similar jump in the
00:42:53
fabrication and what's interesting about this is we're going to be using applied
00:43:00
materials and the modern fabrication processes that they have which on 300 mm
00:43:08
tools you know you can't get in China for example you can get it for camos and then
00:43:14
they're developing we're developing standard processes but you know new recipes and new ways to put it together
00:43:22
and we think by doing that we can do a huge leaprog and then get there faster
00:43:28
and get there in a way that you know will protect our lead. There's other things we're doing too. Uh and you know
00:43:35
that that's a small part of it, but uh you know we think there's a way to um
00:43:40
you know really lead the field and uh and we're happy we have good industrial partners of uh applied materials
00:43:48
synopsis design tools Hula Packard Enterprise some startups who do the
00:43:54
theory work. Uh so you know we have a good consortium and we want to use all
00:44:00
that knowledge and expertise of engineering to make this happen. Where were you when you got the news
00:44:06
this week that you won the Nobel Prize and how surprised were you because this is a 40year-old
00:44:12
research effort. Had anyone giving you a call rumor gossip mill saying, "Hey, you're on the list this year potentially
00:44:18
being considered." So let me uh give you a little bit of the inside story. Um you know if you we
00:44:25
we've known that this was a important experiment from the beginning. we've obtained some other prizes that are you
00:44:32
know much less wellknown and really appreciative of all that and you you
00:44:38
what happens is the Nobel um um system uh put together Nobel symposiums where
00:44:46
they get together physicists in a certain field which is quantum information and this kind of thing and
00:44:53
they they give uh have all the scientists give talks and and they want to kind of check on the vi vitality of
00:45:00
the you know of the field, how big is it? And then you know also maybe some of
00:45:06
the the leaders that maybe think about it, you know, can they give a good talk? Would they good be a good representative?
00:45:12
So um Michelle and John and I have been to these uh symposiums before and we
00:45:19
kind of knew, you know, what was going on, you know, that at least we were considered. And but I I'll just tell you
00:45:25
as a scientist just to be invited to these and be considered is a is a
00:45:31
fantastic honor, you know, and and having getting the prize is just so kind
00:45:38
of unbelievable that you shouldn't think that way. So, you know, I've known about it for a few years. And in fact, to be
00:45:45
very honest, in the past when the dates have come around, it's like, oh, is this going to happen? And then you wake up in
00:45:52
the morning and it's like, "Oh, it didn't happen." And you're kind of down for a day. You know, it didn't happen
00:45:59
this year. And that's a very bad attitude. I I don't like that at all. And, you know, you you should not covet
00:46:05
some, you know, insanely difficult uh prize that, you know, only only goes to
00:46:12
a few people. So, what happened this year is I kind of worked through this over several years and this year I just
00:46:19
kind of forgot about it. Okay. So, I went to bed and then uh and then uh we
00:46:24
got the call at 3:00 and my wife answered the phone and found out what happened. But um she didn't wake me up
00:46:32
right away because she knew if the day was going to be hectic and I needed my sleep to not be grumpy. That
00:46:38
was nice of her. Don't want to be grumpy talking it. So, she woke me up at 5:30 and
00:46:44
you know, as I looked at the computer, oh my god. you know, and then we had some reporters coming over at 6
00:46:50
which, you know, interviewed me, you know, right when I had found out, half hour after I'd found out.
00:46:56
And it's it's a it's it's great. It's it's a great honor and uh it's just been
00:47:02
really fun. And then, you know, I've been getting a lot of emails from people I've worked with or students I've had in
00:47:08
the past congratulating me and you exchange little stories and the like.
00:47:13
and it's it's it's kind of a very special time. That's great. Any um science or
00:47:20
technology fields that you've been following outside of your core discipline that you think are really
00:47:28
exciting. I always like to hear what major kind of thinkers to be honest. I'm just so focused on
00:47:36
doing this and especially when you start a company, you better be focused, right?
00:47:41
So, I'm doing that. But one of the fields that I find, this is someone Ben Mazen at UC Santa Barbara is looking for
00:47:50
exoplanets and they're using superconducting detectors that are somewhat similar to
00:47:57
what we're doing. In fact, in the 1990s or so, I helped, you know, helped
00:48:04
establish that field with other people and did that for five, six, seven years
00:48:10
uh to do that. but he's doing it in a different way. And I really like how, you know, this instrumentation, you
00:48:17
know, that we've been working on is their quantum devices are are now able to um uh do these astronomy
00:48:25
uh detectors and and look for look for these. And of course, there's so much going on in astronomy these way days
00:48:32
with gravitational detectors and exoplanet searches and it it it's just
00:48:38
really fascinating to me. And again it's very much technologyoriented where people are building good detectors. This
00:48:45
is what I like. Okay. I like building building instruments. So that that's particularly interest.
00:48:52
Yeah, that's great. I mean very exciting field and hopefully will develop quantum
00:48:58
computers that will help us build materials and technology to help us get
00:49:03
there one day. So that's right. Many rungs on the ladder of human progress. Well, congratulations again on
00:49:10
winning the Nobel Prize in physics this year. Very welld deserved. It's a fantastic moment. Enjoy it. Enjoy the
00:49:16
ceremony and we're excited for your continued work in the field of material
00:49:21
quantum computing. And thank you. Yeah. And thank you. I really enjoyed the questions and the flow where you
00:49:28
were asking questions to explain it at the right level for people. And uh I I I
00:49:33
really appreciate that. This is a great great podcast. Great. Thank you.
00:49:42
[Music]
00:49:54
I'm going all in.