WEBVTT - The Nobel Winning Trick Behind All Your Devices 0:00:00.200 --> 0:00:02.400 Hey, please take a second and leave us a review 0:00:02.480 --> 0:00:06.279 on Apple Podcasts, Spotify, or wherever you listen to the podcast. 0:00:06.960 --> 0:00:12.720 Thanks a lot. Hey, welcome to Science Stuff production of iHeartRadio. 0:00:13.039 --> 0:00:16.880 I'm horhitch Ham, and today we're doing the impossible. We 0:00:17.120 --> 0:00:22.000 are going to basically teleport through walls, and we're going 0:00:22.079 --> 0:00:25.799 to do this using something called quantum tunneling, which is 0:00:25.840 --> 0:00:29.360 a phenomenon that's being used to make quantum computers a reality. 0:00:29.520 --> 0:00:32.400 Today we're going to talk to a couple of physicists 0:00:32.440 --> 0:00:34.839 about this, including one of the people who want the 0:00:34.880 --> 0:00:38.360 Nobel Price this year for this technology. I'm going to 0:00:38.360 --> 0:00:40.120 ask him what it was like to win and what 0:00:40.240 --> 0:00:44.000 advice he has for future scientists to get ready to 0:00:44.120 --> 0:00:47.280 tunnel to the quantum world. As we answer the question 0:00:47.680 --> 0:00:56.120 what is quantum tunneling? Hey, everyone, Today we're taking another 0:00:56.160 --> 0:01:00.160 trip to the quantum world. We've talked before about what 0:01:00.200 --> 0:01:03.520 a quantum computer is and how it might basically make 0:01:03.600 --> 0:01:07.920 passwords and things like cryptocurrency totally useless. Today we are 0:01:07.959 --> 0:01:11.440 covering how those quantum computers are being made, and most 0:01:11.480 --> 0:01:14.280 of the big ones, like the ones at Google and Amazon, 0:01:14.720 --> 0:01:19.240 use something called macroscopic quantum tunneling. So we're going to 0:01:19.280 --> 0:01:21.960 explore what that is. And the cool thing is that, 0:01:22.080 --> 0:01:25.039 thanks to a collaboration with Physics magazine, we're going to 0:01:25.040 --> 0:01:27.120 talk to one of the people who won the Nobel 0:01:27.200 --> 0:01:30.200 Prize for it this year. But before we do that, 0:01:30.280 --> 0:01:33.319 I reached out to doctor Shohini Ghosch, a professor of 0:01:33.319 --> 0:01:36.840 physics and computer science at Wilfred Laurier University and the 0:01:36.920 --> 0:01:41.480 chief Technology officer at the Quantum Algorithms Institute in Canada. 0:01:41.600 --> 0:01:44.280 I asked her to help us explain what quantum and 0:01:44.560 --> 0:01:49.440 quantum tunneling are. Well, thank you, doctor Ghosh for talking 0:01:49.480 --> 0:01:49.680 with me. 0:01:50.120 --> 0:01:52.400 I'm glad too, thank you for inviting me. 0:01:52.720 --> 0:01:54.880 So maybe for those of us who are not familiar, 0:01:55.000 --> 0:01:56.960 how do you describe what quantum is? 0:01:57.240 --> 0:02:02.360 Yeah, so, quantum mechanics is actually the theory that underpins 0:02:02.400 --> 0:02:07.040 the behavior of fundamental particles and light in the universe. So, 0:02:07.080 --> 0:02:09.720 for example, if you look at the periodic table, there's 0:02:09.760 --> 0:02:12.720 a whole bunch of elements, but all of those items 0:02:12.720 --> 0:02:16.240 are also built up of fundamental particles like electrons. And 0:02:16.280 --> 0:02:18.280 if you look at the nucleus, there are particles within 0:02:18.320 --> 0:02:22.160 the nucleus too. Every single such microscopic particle in the 0:02:22.240 --> 0:02:25.680 universe we can actually describe using this amazing theory called 0:02:25.760 --> 0:02:29.200 quantum mechanics, and we can describe even particles of light, 0:02:29.280 --> 0:02:32.320 which we call photons. So essentially this is our description 0:02:32.520 --> 0:02:34.680 of all the matter and energy in the universe. 0:02:34.680 --> 0:02:38.040 It's no big deal, right, That's a small theory. I 0:02:38.040 --> 0:02:39.760 guess you could say, oh, yeah, yeah. 0:02:39.919 --> 0:02:42.200 The other important thing I'd wanted to say about quantum 0:02:42.200 --> 0:02:45.120 mechanics is that we feel like this might be something 0:02:45.720 --> 0:02:48.720 not connected to our everyday lives. But think about one 0:02:48.760 --> 0:02:51.920 of those very very important elements in that periodic table, 0:02:52.240 --> 0:02:56.760 which is silicon. Understanding silicon is essentially why we now 0:02:56.800 --> 0:03:01.359 have Silicon Valley, semiconductor industry, all of our electronics, all 0:03:01.400 --> 0:03:04.720 the devices we use every day. So it's actually part 0:03:04.800 --> 0:03:07.600 of our lives. And we've been involved in this amazing 0:03:07.639 --> 0:03:11.119 technology revolution which started back one hundred years ago when 0:03:11.160 --> 0:03:13.120 this theory was first developed. 0:03:13.360 --> 0:03:16.960 Amazing and phones are definitely a big part of my 0:03:17.040 --> 0:03:19.840 teenagers's lives. Maybe sometimes too. 0:03:19.800 --> 0:03:23.040 Much, that's true, There could be too much quantum mechanics 0:03:23.040 --> 0:03:24.520 in some people's lives. 0:03:26.720 --> 0:03:29.799 Okay, So things at the level of super small particles 0:03:30.000 --> 0:03:33.880 act very differently from what we experience in our everyday lives. 0:03:34.440 --> 0:03:37.040 They have strange properties that you might have heard of before, 0:03:37.440 --> 0:03:40.120 like the idea that you can never tell exactly where 0:03:40.160 --> 0:03:43.520 they are and where they're going. That's called the Heisenberg 0:03:43.640 --> 0:03:47.040 uncertainty principle. Or that they have a probability of being 0:03:47.080 --> 0:03:50.680 in several places at the same time. That's called superposition. 0:03:51.040 --> 0:03:54.080 And there's something called entanglement, which is the idea that 0:03:54.120 --> 0:03:57.480 these weird quantum properties can spread out when you mix 0:03:57.520 --> 0:04:01.280 different quantum things together. Well, a result of some of 0:04:01.280 --> 0:04:04.720 these properties is something called quantum tunneling. 0:04:05.720 --> 0:04:09.640 So quantum tunneling is a very very fundamental property that's 0:04:09.680 --> 0:04:11.880 part of this model, and what it is is it 0:04:11.920 --> 0:04:15.680 describes the behavior of these quantum particles. It's kind of 0:04:15.720 --> 0:04:18.760 like walking through walls. I don't advise anybody to try 0:04:18.800 --> 0:04:22.400 it in our real world, but yes, electrons and other 0:04:22.480 --> 0:04:25.120 quantum particles can do it, and that's quantum tunneling. 0:04:25.720 --> 0:04:29.160 Okay, here's how doctor Goes explains what quantum tunneling is. 0:04:29.640 --> 0:04:32.159 Let's say you're standing in front of a mountain. Now 0:04:32.480 --> 0:04:34.320 you are where you are, but if you were a 0:04:34.440 --> 0:04:38.480 quantum particle, where you're going to be is kind of fuzzy. 0:04:39.040 --> 0:04:41.400 There's a probability that you're going to be one meter 0:04:41.440 --> 0:04:44.279 ahead of you, and another probability that you're going to 0:04:44.279 --> 0:04:48.039 be two meters ahead or three meters behind. That cloud 0:04:48.120 --> 0:04:52.120 of possibilities is called a wave function. You can think 0:04:52.120 --> 0:04:54.479 of it as kind of a fog or a cloud 0:04:54.520 --> 0:04:57.479 that hovers around you that tells you where you might 0:04:57.520 --> 0:05:01.320 be next. Well, mathematically, part of that cloud could be 0:05:01.560 --> 0:05:04.680 on the other side of that mountain in front of you. 0:05:04.680 --> 0:05:07.599 Your wave function can sort of leak to the other side, 0:05:07.839 --> 0:05:10.960 and so there's a wisp of a possibility that's where 0:05:10.960 --> 0:05:13.040 you're going to be next. So if you stand in 0:05:13.040 --> 0:05:16.440 front of that mountain long enough or enough times, you 0:05:16.520 --> 0:05:20.359 might suddenly find yourself appearing on the other side without 0:05:20.480 --> 0:05:22.159 having to climb the mountain. 0:05:23.200 --> 0:05:26.599 If that electron doesn't have that energy, then it shouldn't 0:05:26.600 --> 0:05:28.280 be able to climb to the top of the mountain, 0:05:28.560 --> 0:05:31.120 and yet it can make it to the other side. 0:05:31.360 --> 0:05:35.000 So this very surprising way to somehow be able to 0:05:35.120 --> 0:05:37.880 not have the energy and still be able to walk 0:05:37.920 --> 0:05:39.960 through the mountain because there's no way it can climb 0:05:40.000 --> 0:05:42.559 to the top since it doesn't have the energy. That's 0:05:42.600 --> 0:05:45.160 what quantum tunneling is. It's like if we walk through 0:05:45.200 --> 0:05:46.080 the mountain. 0:05:46.120 --> 0:05:48.680 Or it's like we created a tunnel through the mountain 0:05:48.960 --> 0:05:51.680 that's not really there. It's a quantum tunnel exactly. 0:05:51.760 --> 0:05:54.560 There's actually no probability of being inside the mountain. 0:05:55.600 --> 0:05:58.760 Okay, this is the strange part. It's not like you 0:05:59.040 --> 0:06:02.360 or the particle go through the mountain, because if you do, 0:06:02.640 --> 0:06:05.159 that would mean you're inside the mountain at some point. 0:06:05.680 --> 0:06:09.240 It really is like you just appear on the other side. 0:06:09.880 --> 0:06:12.760 What's really weird about this quantum tunnel is that if 0:06:12.760 --> 0:06:16.720 you ever try to observe this particle tunneling through this mountain, 0:06:16.760 --> 0:06:20.320 you'll never find it actually ever spending any time inside 0:06:20.320 --> 0:06:22.560 the mountains. It's either on one side or the other, 0:06:23.120 --> 0:06:26.240 but it's never actually in the mountain. So that's what 0:06:26.440 --> 0:06:31.039 makes it even weirder. Okay, every time you think quantum 0:06:31.160 --> 0:06:33.080 is not weird, it gets even weirder. 0:06:35.440 --> 0:06:37.880 Okay, you might be wondering at this point, like I was, 0:06:38.080 --> 0:06:40.760 how is this possible? How can something just be on 0:06:40.880 --> 0:06:43.440 one side of the mountain in one moment and then 0:06:43.480 --> 0:06:45.280 be on the other side of the mountain in the 0:06:45.320 --> 0:06:49.839 next moment. That seems impossible. Well, interestingly, that's something not 0:06:49.920 --> 0:06:55.039 even people who study quantum physics all their lives can't explain. Well, 0:06:55.080 --> 0:06:57.359 why do I have a probability of being on the 0:06:57.400 --> 0:06:59.800 other side of the mountain If it's impossible. 0:06:59.279 --> 0:07:01.320 Well, I'm not saying is the next instance. It could 0:07:01.320 --> 0:07:03.960 take some time before you find the particle on the 0:07:03.960 --> 0:07:06.520 other side, but what it's doing during that time is 0:07:06.560 --> 0:07:09.320 not to dwell inside the mountain. When you say, why 0:07:09.360 --> 0:07:10.040 does it do it? 0:07:10.320 --> 0:07:10.920 That is the. 0:07:10.880 --> 0:07:15.240 Great mystery of quantum mechanics. Our theory tells us that 0:07:15.560 --> 0:07:19.360 this is how the description when we go and do experiments, 0:07:19.640 --> 0:07:22.040 so when we go and measure it, we can confirm 0:07:22.080 --> 0:07:24.600 whether the theory is correct or not. So in a way, 0:07:24.640 --> 0:07:28.160 the universe is showing us that this is how it works. 0:07:28.760 --> 0:07:31.880 In this universe, these kinds of robberties are possible and 0:07:31.920 --> 0:07:35.320 we can observe it. And if all this sounds very confusing, 0:07:35.440 --> 0:07:39.000 it's okay because I think quantum scientists and physicists since 0:07:39.080 --> 0:07:42.360 the early nineteen hundreds, this is something physicists have also 0:07:42.360 --> 0:07:46.720 debated about. Is this particle actually just disappearing and appearing 0:07:47.040 --> 0:07:50.160 on two sides of a barrier? How come it doesn't 0:07:50.160 --> 0:07:52.720 spend time in the barrier. These are still things that 0:07:52.760 --> 0:07:53.560 we are grappling with. 0:07:53.880 --> 0:07:56.680 So not even Einstein figured out what it all means. 0:07:56.920 --> 0:08:01.520 No, I think Einstein was always deeply disturbed the implications 0:08:01.560 --> 0:08:02.320 of this serial. 0:08:02.400 --> 0:08:05.640 He wasn't able to quantum tunnel out of No, that's 0:08:05.680 --> 0:08:06.200 good work. 0:08:06.280 --> 0:08:07.640 Yes, he was unable to. 0:08:09.160 --> 0:08:12.800 Okay, two recap. This is what quantum tunneling is. It's 0:08:12.800 --> 0:08:17.120 a phenomenon that you see quantum particles like electrons or protons, 0:08:17.320 --> 0:08:19.640 where if you have a particle that's up against a 0:08:19.760 --> 0:08:23.680 wall or some kind of energy barrier, that particle can 0:08:23.720 --> 0:08:26.760 sort of tunnel through that wall and appear on the 0:08:26.760 --> 0:08:30.280 other side if there is a mathematical probability that it 0:08:30.320 --> 0:08:33.959 can do that. Even though it may seem physically impossible, 0:08:34.520 --> 0:08:37.440 physicists aren't quite sure how it happens, but it does, 0:08:37.920 --> 0:08:41.120 and it's all around us. It's what makes scanning tunneling 0:08:41.200 --> 0:08:45.840 microscopes work. And flash memory, which basically every phone and 0:08:45.920 --> 0:08:50.040 computer in the world uses. Flash memory works by pushing 0:08:50.080 --> 0:08:54.000 electrons to quantum tunnel in and out of little electronic 0:08:54.120 --> 0:08:58.480 cages that are completely insulated. When an electron is inside 0:08:58.480 --> 0:09:01.680 the cage, it's storing in of one and it stays 0:09:01.720 --> 0:09:05.400 there until you quantum tunnel it out. The device you're 0:09:05.480 --> 0:09:09.600 using right now most likely uses quantum tunneling to store 0:09:09.640 --> 0:09:12.760 the audio file you're listening to right now. And all 0:09:12.800 --> 0:09:16.480 of this raises two questions. One, if quantum particles can 0:09:16.480 --> 0:09:20.240 tunnel through walls and barriers, could bigger objects do it too? 0:09:20.880 --> 0:09:23.880 And two, if bigger things can do this tunneling, what 0:09:24.040 --> 0:09:26.600 can you do with them? Well, as it turns out, 0:09:26.760 --> 0:09:30.200 this year's Nobel Prize for Physics was awarded to three 0:09:30.240 --> 0:09:33.760 scientists who prove that this is possible and who are 0:09:33.880 --> 0:09:38.320 using it to make quantum computers. So when we come back, 0:09:38.400 --> 0:09:40.080 we're going to talk to one of the winners to 0:09:40.200 --> 0:09:42.560 hear how they did it, and I'm going to ask 0:09:42.600 --> 0:09:45.880 them what's it like to win a Nobel prize. Stay 0:09:45.920 --> 0:09:47.680 with us, we'll be right back. 0:09:59.200 --> 0:09:59.760 Welcome back. 0:10:01.320 --> 0:10:04.400 We're talking about quantum tunneling, which is something that happens 0:10:04.440 --> 0:10:08.120 in the quantum world. Small particles like electrons can sort 0:10:08.160 --> 0:10:11.160 of tunnel through walls and appear on the other side 0:10:11.160 --> 0:10:14.520 of them, almost by magic. And as I mentioned, it's 0:10:14.520 --> 0:10:17.800 what's used in scanning tunneling microscopes to take pictures of 0:10:17.800 --> 0:10:20.640 extremely small things, and it's how flash memory in your 0:10:20.679 --> 0:10:25.480 phone and computers work now. For a long time, people 0:10:25.520 --> 0:10:28.840 thought that this strange behavior could only happen for small 0:10:28.920 --> 0:10:32.679 particles like single electrons or protons, and that once you 0:10:32.800 --> 0:10:36.040 got to bigger things, things made of millions or billions 0:10:36.040 --> 0:10:40.719 of particles, this behavior couldn't happen because of something called decoherence, 0:10:41.160 --> 0:10:45.200 which basically means the quantum information is lost. But in 0:10:45.280 --> 0:10:48.760 nineteen eighty four, three physicists at the University of California 0:10:48.760 --> 0:10:53.000 at Berkeley showed that this assumption was wrong, and for 0:10:53.040 --> 0:10:56.199 that this year they got the Nobel Prize in Physics. 0:10:56.480 --> 0:10:59.319 To tell us what happened, here's doctor John Martinez, one 0:10:59.360 --> 0:11:03.640 of the three Pece people who won the price. Well, 0:11:03.679 --> 0:11:06.240 thank you so much, doctor Martinez for joining us. It's 0:11:06.280 --> 0:11:08.320 such a pleasure and an honor to be speaking with you. 0:11:08.480 --> 0:11:09.120 Yeah, thank you. 0:11:09.320 --> 0:11:11.520 Could you tell us just generally who you are and 0:11:11.559 --> 0:11:12.040 what do you do? 0:11:12.160 --> 0:11:17.480 Well, okay, John Martinez. I've been a physicist researching quantum 0:11:17.559 --> 0:11:22.280 devices quantum computing for many decades. Right now, I was 0:11:22.320 --> 0:11:26.800 a professor at UC Santa Barbara. I've retired recently. I 0:11:26.880 --> 0:11:31.320 also worked for the Google Quantum AI team until about 0:11:31.360 --> 0:11:34.160 twenty twenty and for a couple of years. Now I've 0:11:34.200 --> 0:11:37.679 started my own company called Collab, and I'm the chief 0:11:37.720 --> 0:11:41.559 technology officer and we're just basically trying to build a 0:11:41.679 --> 0:11:42.880 useful quantum computer. 0:11:43.160 --> 0:11:44.280 It sounds like you're very busy. 0:11:44.440 --> 0:11:48.800 Ah, yes, I'm super busy right now after the Nobel Prize. 0:11:48.840 --> 0:11:52.600 But it's been nice, it's been wonderful. I can't complain. 0:11:52.840 --> 0:11:55.560 What was it like to receive the announcement that you 0:11:55.600 --> 0:11:56.600 had won the prize? 0:11:56.679 --> 0:12:00.480 Well, I wasn't expecting it at all, and this I 0:12:00.559 --> 0:12:03.160 was just so busy. I knew something was coming up, 0:12:03.160 --> 0:12:06.080 but I then thought about the date or anything. And 0:12:06.280 --> 0:12:09.480 actually my wife found out about it through email. She 0:12:09.640 --> 0:12:11.760 was up late and then she let me sleep in 0:12:11.920 --> 0:12:16.720 till five thirty in the morning, which I love my wife. 0:12:16.760 --> 0:12:20.040 She knows exactly what I need. I need my sleep. Yeah, 0:12:20.040 --> 0:12:22.480 And then she just woke me up in bed and said, hey, 0:12:22.520 --> 0:12:25.040 there's some reporters outside you want to talk to you. 0:12:26.080 --> 0:12:28.800 And it was like, what, okay, you know, so I 0:12:28.840 --> 0:12:31.559 looked on I opened my computer and you know, lo 0:12:31.760 --> 0:12:35.679 and behold with John Clark and Michelle Deverey, and there 0:12:35.760 --> 0:12:38.520 was the announcement with me, So that was just a 0:12:38.559 --> 0:12:41.440 great honor. And it just took a kind of stunned 0:12:41.960 --> 0:12:44.839 for a few minutes and kind of got ready and 0:12:45.440 --> 0:12:48.040 I talked to some reporters. He showed up early in 0:12:48.080 --> 0:12:51.440 the morning to film me and get my immediate reaction 0:12:51.679 --> 0:12:55.920 and the like. But yeah, it's you do science because 0:12:56.040 --> 0:13:00.160 it's great, it's interesting. There's an artistic element to it. 0:13:00.240 --> 0:13:04.640 There's a communication element, answering questions all that's really fun. 0:13:04.920 --> 0:13:08.040 But you know, getting this award is an honor, not 0:13:08.040 --> 0:13:11.920 not something one should expect. Okay, that's the best way 0:13:11.960 --> 0:13:12.679 to approach it. 0:13:12.920 --> 0:13:15.439 Amazing live go back to you when you first did 0:13:15.480 --> 0:13:18.679 the experiment, right, and I believe at the time quantum 0:13:18.679 --> 0:13:23.200 tunneling had been proven for small particles electrons, that was 0:13:23.240 --> 0:13:25.920 well known. To take us back to before you did 0:13:26.000 --> 0:13:29.600 the experiment, somebody had proposed that it might be possible 0:13:29.760 --> 0:13:33.640 to prove quantum properties in more complicated systems, but it 0:13:33.679 --> 0:13:35.640 was a big unknown. What were you thinking at the 0:13:35.640 --> 0:13:36.880 time you and your colleagues. 0:13:37.200 --> 0:13:41.000 First of all, I decided to join John Clark's group 0:13:41.120 --> 0:13:44.640 as a graduate student. That was in nineteen eighty because 0:13:44.679 --> 0:13:49.080 he was already doing experiments seeing quantum noise effects in 0:13:49.160 --> 0:13:53.720 electrical devices. And I thought this was really fascinating because 0:13:53.880 --> 0:13:57.520 I liked electronics. I like devices, that was my hobby 0:13:57.600 --> 0:14:01.600 and whatever, and of course quantum mechanics fascinating. So I 0:14:01.640 --> 0:14:05.080 went to a conference down in UCLA and it was 0:14:05.160 --> 0:14:08.480 clear people were talking about it was really interesting, but 0:14:08.760 --> 0:14:12.520 people really didn't understand the experiment very well yet. 0:14:12.720 --> 0:14:13.640 Oh what was the question? 0:14:13.920 --> 0:14:17.560 Well, the question was could you see this macroscopic quantum 0:14:17.640 --> 0:14:18.440 tunneling effect? 0:14:19.120 --> 0:14:22.640 Okay, here's the question, doctor Martinez, doctor John Clark, and 0:14:22.680 --> 0:14:26.600 doctor Michelle Deveray. Where tackling was could you get something 0:14:26.720 --> 0:14:30.440 bigger than an electron, maybe something millions of times bigger 0:14:30.800 --> 0:14:35.200 to quantum tunnel So instead of having one electron passing 0:14:35.240 --> 0:14:38.120 through a wall and appearing on the other side, could 0:14:38.200 --> 0:14:41.080 you get a whole bunch of them acting together to 0:14:41.200 --> 0:14:41.880 tunnel through. 0:14:42.960 --> 0:14:45.760 And at the time, it was just murky and not 0:14:46.000 --> 0:14:48.360 very clear in the light. And I remember talking to 0:14:48.440 --> 0:14:51.240 John Clark about that and he said, yeah, well, there 0:14:51.240 --> 0:14:54.320 were some experiments that are already done, but you know, 0:14:54.320 --> 0:14:55.800 if we're going to do this, we're going to have 0:14:55.840 --> 0:14:56.800 to do something new. 0:14:57.360 --> 0:15:00.360 How did you go about designing this experiment? He said, 0:15:00.360 --> 0:15:01.280 something new was needed. 0:15:01.440 --> 0:15:04.640 So what the experiment is very simple. You'll have this 0:15:04.840 --> 0:15:08.560 weak link adjosin junction and you put current through it, 0:15:08.720 --> 0:15:12.120 so in some condition it looks like a superconductor. And 0:15:12.160 --> 0:15:14.560 then as you raise the current more and more, at 0:15:14.600 --> 0:15:18.040 some point it switches to the voltage state. Okay, it 0:15:18.080 --> 0:15:19.680 looks like a normal metal wire. 0:15:20.800 --> 0:15:23.080 This is a little hard to explain, but it's basically 0:15:23.080 --> 0:15:26.680 the same picture we had before. Imagine a wire where 0:15:26.680 --> 0:15:29.200 you have electrons flowing through it, but now in the 0:15:29.240 --> 0:15:31.920 middle of the wire you put up a wall, a 0:15:32.000 --> 0:15:35.640 thin piece of something that doesn't conduct electricity. So now 0:15:35.720 --> 0:15:39.920 the electrons can flow through the wire unless the quantum 0:15:39.960 --> 0:15:44.120 tunnel through the wall. Now, as I mentioned, getting one 0:15:44.160 --> 0:15:48.240 electron to quantum tunnel through is not that hard. Happens 0:15:48.240 --> 0:15:50.480 all the time on the flash memory of your phone. 0:15:50.840 --> 0:15:53.880 But that's only one electron at a time. To get 0:15:53.920 --> 0:15:57.280 more than one electron tunnel at the same time, you 0:15:57.320 --> 0:16:00.280 need to make the wire a super conduct. 0:16:02.080 --> 0:16:04.960 All the electrons in a normal mettle are kind of 0:16:04.960 --> 0:16:09.560 moving around independently. But what happens is when you go 0:16:09.680 --> 0:16:14.560 into the superconducting state, they lock together and it's like 0:16:14.720 --> 0:16:19.200 they condense into what it's called a BCS state. Then 0:16:19.560 --> 0:16:23.440 it behaves like a single it's a ball if you like. 0:16:24.040 --> 0:16:27.880 So you really needed the superconducting state to see a 0:16:27.920 --> 0:16:29.120 macroscopic state. 0:16:30.840 --> 0:16:33.240 This gets a bit technical, but if you make your 0:16:33.280 --> 0:16:36.600 wire a superconductor by making it out of a special 0:16:36.640 --> 0:16:40.080 material and making it super cold, then all the electrons 0:16:40.080 --> 0:16:42.800 and the wire start to sort of bunch together and 0:16:42.840 --> 0:16:45.760 they get linked in a quantum mechanical way so that 0:16:45.800 --> 0:16:50.120 they act like one giant electron. And that's what doctor 0:16:50.160 --> 0:16:53.760 Martinez and his colleagues were able to show. Can quantum 0:16:53.760 --> 0:16:57.160 tunnel not just one electron or a pair of electrons, 0:16:57.520 --> 0:17:01.680 but a synchronized blob of millions of electrons. Now the 0:17:01.720 --> 0:17:05.320 secret sauce here was two things. One they added some 0:17:05.560 --> 0:17:08.639 new bells and whistles to the experiment that nobody had 0:17:08.680 --> 0:17:12.920 tried before, better filters in a microwave resonator. And two 0:17:13.359 --> 0:17:18.240 they had a lot of moxie. I love to ask 0:17:18.240 --> 0:17:20.119 you about the moment of discovery. 0:17:20.520 --> 0:17:24.040 Well, the moment of discovery was when we did this 0:17:24.240 --> 0:17:27.840 initial experiment it didn't work, and then we discovered how 0:17:27.840 --> 0:17:30.440 to fix it, and then we got it to work, 0:17:30.600 --> 0:17:32.880 and that's when we really felt we were going to 0:17:33.080 --> 0:17:35.320 get this to work. And then it just took a 0:17:35.359 --> 0:17:38.680 lot of effort to get it to work and understand everything. 0:17:39.000 --> 0:17:40.959 It took some time to get there, but you just 0:17:41.119 --> 0:17:43.680 did experiment after experiment and it made. 0:17:43.560 --> 0:17:46.439 Sense interesting, and so you didn't give up. Do you 0:17:46.440 --> 0:17:48.880 remember that moment where you're lifted on You're like, oh, 0:17:48.960 --> 0:17:49.520 it's working. 0:17:49.960 --> 0:17:52.439 Yeah, I kind of remember that, the one of this 0:17:52.600 --> 0:17:57.000 initial experiment us being very pleased with that. The one 0:17:57.080 --> 0:18:00.840 moment I do remember is we were just from turning 0:18:00.880 --> 0:18:03.840 on that sample, cooled it down, I set it up, 0:18:03.880 --> 0:18:06.879 and I had an assilloscope that was tracing when it 0:18:07.000 --> 0:18:10.399 switched from the zero voltage to the vaulted state, and 0:18:10.480 --> 0:18:13.560 I could see those three peaks. Okay, up until then, 0:18:13.600 --> 0:18:17.239 I only saw one peak. Those three peaks are just 0:18:17.280 --> 0:18:21.280 the smoking gun of quantum mechanics, to have three distinct 0:18:21.320 --> 0:18:25.600 frequencies in this system, and that's a property of quantum 0:18:25.640 --> 0:18:28.919 mechanics that tells you there's something very unusual going on 0:18:29.320 --> 0:18:33.119 with this kind of wave nature. Okay, there's something you know, 0:18:33.400 --> 0:18:36.480 really quantum going on there. But when I saw those 0:18:36.520 --> 0:18:39.560 three peaks. I knew that when I analyzed the data, 0:18:40.000 --> 0:18:43.800 this would be a totally clear explanation what was going on. 0:18:44.480 --> 0:18:48.560 So I do remember the joy of seeing that and 0:18:48.680 --> 0:18:52.000 knowing that you know, this would be the really conclusive 0:18:52.040 --> 0:18:54.280 proof that it was the main quantum mechanics. 0:18:55.640 --> 0:19:00.399 So that's the story of a Nobel Price winning discovery. Next, 0:19:00.440 --> 0:19:03.439 we're gonna talk about what was so significant about this 0:19:03.560 --> 0:19:07.040 discovery and how it's creating a boom in the rays 0:19:07.080 --> 0:19:12.840 to create the first really functional quantum computer. Stay with us, 0:19:13.359 --> 0:19:30.920 we'll be right back, and we're back. We're talking about 0:19:31.000 --> 0:19:33.960 quantum tunneling. And we just heard one of the winners 0:19:34.000 --> 0:19:37.199 of this year's Nobel Prize in physics describe how he 0:19:37.400 --> 0:19:40.000 and his colleagues were able to prove that the weird 0:19:40.000 --> 0:19:43.200 properties of quantum physics don't just happen at the level 0:19:43.280 --> 0:19:47.240 of single particles like electrons or protons. If you set 0:19:47.280 --> 0:19:50.800 things up right, you can see quantum properties in bigger objects, 0:19:50.960 --> 0:19:53.600 big enough to hold in your hand. Now the question 0:19:53.760 --> 0:19:57.359 is what can you do with that. Here's Professor Shohini Coach. 0:19:58.480 --> 0:20:01.520 So we've been talking about fundamental and small particles, but 0:20:01.640 --> 0:20:05.439 this year's Nobel Price went to a quantum tunneling of 0:20:05.800 --> 0:20:10.840 bigger things, things that are bigger than microscopic objects exactly. 0:20:11.000 --> 0:20:15.040 So the reason that this was an important step was 0:20:15.119 --> 0:20:18.199 not because this was anything new about tunneling. This was 0:20:18.240 --> 0:20:22.240 something that was perhaps the next step in a long 0:20:22.359 --> 0:20:28.280 series of theoretical and experimental studies that were exploring quantum effects. 0:20:28.440 --> 0:20:31.600 But all of those were being done at that very 0:20:31.720 --> 0:20:35.760 very small, individual particle level. So measuring the current generated 0:20:35.800 --> 0:20:38.960 by one electron is extremely difficult, but measuring the current 0:20:39.200 --> 0:20:43.000 generated by a million is a million times higher current, 0:20:43.240 --> 0:20:48.920 So that immediately makes the engineering piece much much easier. 0:20:49.040 --> 0:20:51.200 Well, first of all, thank you for making things easier 0:20:51.240 --> 0:20:55.679 for engineers. I'm an engineer. We always appreciate when the 0:20:55.680 --> 0:20:58.040 physical world is easier to design for. 0:20:58.520 --> 0:21:01.360 So I think the big advance was it led to 0:21:01.400 --> 0:21:05.280 this new possibility of creating devices and doing engineering at 0:21:05.280 --> 0:21:09.040 a larger scale, and that would lead to technologies for 0:21:09.119 --> 0:21:10.840 the future, and that's really what happened. 0:21:12.240 --> 0:21:15.200 So the big breakthrough here is in making it easier 0:21:15.400 --> 0:21:19.119 to make quantum devices. As we said, quantum objects have 0:21:19.200 --> 0:21:23.280 some strange properties that almost seem like magic, and before 0:21:23.359 --> 0:21:26.040 this discovery, we thought the only way to make them 0:21:26.359 --> 0:21:30.840 was by handling and manipulating hiny, little fragile particles or 0:21:30.960 --> 0:21:35.040 individual atoms. But what doctor Martinez and his colleagues discovered 0:21:35.359 --> 0:21:38.000 was that you can get that same quantum magic with 0:21:38.240 --> 0:21:41.959 larger objects that are easier to work with and put together. 0:21:42.480 --> 0:21:45.159 And one of the biggest applications so far is in 0:21:45.320 --> 0:21:49.320 making quantum computers. If you're interested in learning more about 0:21:49.400 --> 0:21:52.200 quantum computers, we did a whole episode on them earlier 0:21:52.200 --> 0:21:55.640 this year, so check that out. But the main takeaway 0:21:55.720 --> 0:21:58.639 is that quantum computers could be used for lots of 0:21:58.720 --> 0:22:03.640 interesting applications, including breaking encryption, which would make all your 0:22:03.640 --> 0:22:07.919 passwords and all that cryptocurrency out there useless. And the 0:22:07.920 --> 0:22:11.560 idea here is that you can build quantum computers using 0:22:11.680 --> 0:22:17.439 the very same devices that the Nobel Price winning researchers made. 0:22:17.480 --> 0:22:21.320 This became the basis for creating all kinds of devices, 0:22:21.640 --> 0:22:24.920 the most important of those being what we call these 0:22:25.000 --> 0:22:28.600 quantum computing devices that are new types of computers that 0:22:28.800 --> 0:22:33.399 use these superconducting circuits as a fundamental unit of what 0:22:33.440 --> 0:22:35.720 we call a quantum bit, which is, like, you know, 0:22:35.720 --> 0:22:38.960 we have regular bits that drive our regular computers. Quantum 0:22:39.000 --> 0:22:42.480 bits are what are driving our quantum computers. So big 0:22:42.520 --> 0:22:46.440 companies now like IBM and Google and others are using 0:22:46.480 --> 0:22:50.040 that same idea to build out these quantum devices. 0:22:50.480 --> 0:22:54.600 So this has led to an enormous field of people 0:22:54.680 --> 0:22:57.640