Stefanie Tompkins

Transcript

Meenakshi Singh: 

Quantum technologies are already enabling us to do a lot of things that we cannot do with just classical devices. Because transistors and MRI machines, lasers, these are all quantum technologies. Even your classical computers need quantum mechanics to work. But the reason why its becoming particularly relevant right now is that we have the technology to actually access it. So that’s why people feel that we are on the brink of a big explosion of new information, new discoveries, and new inventions. 

Meenakshi Singh: 

My name is Meenakshi Singh. I am an assistant professor in the department of physics at the Colorado School of Mines. 

The Conveyor: 

Youre listening to The Conveyor, the podcast that brings you the latest research, new discoveries and worldchanging ideas from Colorado School of Mines.  

The Conveyor: 

We are seeing a surge in quantum research. Whats the story behind this? 

Meenakshi Singh: 

The first surge quantum came about, I dont know, 60, 70 years ago. And that was based on just understanding quantum coherence—that some entities have this behavior which macroscopic classical things that we are normally used to in the normal world do not have. And that led to the first quantum revolution. You’ll often see this terminology talking about quantum 1.0 and quantum 2.0. So this is referring to quantum 1.0, where we made transistors and lasers and things like that. Now this realization has become relevant that when quantum entities interact with each other, there is something unique that comes from that interaction. 

Meenakshi Singh: 

And youll keep hearing about quantum entanglement. So the ability to generate and control quantum entanglement is supposed to bring us this second revolution, which everyone calls quantum 2.0 commonly. We have known about entanglement for 100 years. But the reason why its becoming particularly relevant right now is that we have the technology to actually access it. So in the last 30, 40 years, we have developed electron microscopy, and theres been a lot of development in microwave electronics, in lasers, in single atom manipulation and measurement. So basically we are at the stage where we can control individual atoms, generate these entanglements, measure these entanglements and actually think about doing something useful for them.  

The Conveyor: 

Okay. So what does the future look like for quantum? 

Meenakshi Singh: 

So the question when people say that, What can we do with quantum in the near future? Theyre often specifically asking about a very general quantum computer. When will we build a quantum computer that is clearly better than a classical computer and that can solve problems that we are not being able to solve using a classical computer? So on that question, thats an interesting question on the quantum computing end. As you know, probably Google demonstrated quantum supremacy using a 50 qubit computer last year on a little toy problem. So we have 50 qubit computers already. The trapped ion computers are also in that 50 qubits range. To really be at the point where youre surpassing classical digital computers you need maybe 100, maybe 500 qubit completely fault-tolerant quantum computer, which is not where we are at right now. So this is very much like an open question right now. And people are working on it and trying to figure out what are the questions that we should be asking of these machines. 

The Conveyor: 

What exactly is the difference between classical computers and quantum computers? 

Meenakshi Singh: 

Yeah. So quantum computers are supposed to be good at solving a specific set of problems better than classical computers. And the classic example of it that you keep hearing about is integer factorization for which there is that very famous Shors algorithm, which shows that a quantum computer can do it efficiently and a classical computer cannot. But its not that they can solve all problems faster than a classical computer. So its only rare that massive parallel processing is useful and its not in all problems. But its only a certain class of problems where they are faster and not all problems. So its not like one day all our classical computers will be gone and well have only quantum computers. Thats not going to happen. 

The Conveyor: 

So youre saying quantum computing wont make my YouTube stream faster?  

Meenakshi Singh: 

I dont think so. But I dont know what all goes into making YouTube work. If making YouTube streaming requires integer factorization, then it might. And if it doesnt, then it wont. 

The Conveyor: 

On the vast spectrum of quantum, what does your research focus on? 

Meenakshi Singh: 

My project basically is focused on how entanglement propagates. So if you have a quantum computer with 10 qubits and all of the qubits talk to each other and their correlations with each other are essential to making that quantum computer work. If theyre not entangled at all, then you cant really do anything with that quantum computer. So the entanglement between different qubits is essential to making that quantum computer work. And my project is focused on how does entanglement propagate in complex networks of qubits. And that will probably help the field in figuring out how to make quantum computers faster for example, what are the optimal couplings, things like that. So that is one project. The other project that Im working on is focused on silicon spin qubits. So one of the things that youll hear a lot when you read about quantum computing is quantum coherence and how qubits keep losing coherence. 

The Conveyor: 

Real quick, just to confirm, coherence in a lay explanation is the desired property of a qubit in order to make a comparison between qubits in a quantum state. 

Meenakshi Singh: 

Oh yeah, totally. Totally. Yeah, because a qubit is only useful as long as it retains quantum coherence. Once it loses quantum coherence, then you can no longer do anything useful from it. And you have to start over again. So coherence times for these qubits are typically very small. They can lose quantum coherence for a lot of reasons, which is why most of them need to be operated at really low temperatures to prevent thermal noise from taking away quantum coherence. So this project is focused on basically how qubits can lose quantum information by interacting with phonons. Phonons are lattice vibrations caused by heat and how we can minimize this by doing some nano structuring, et cetera. And that project is probably going to be relevant to raising qubit operation temperature, which is another big challenge in the field of quantum computing. Whenever you see quantum computing news, you will see a gold-plated dilution refrigerator in the background. And that is just be needing to run it at 10 milli-Kelvins is a major hurdle to scaling up. 

The Conveyor: 

Is your work in relation to superconductors? 

Meenakshi Singh: 

Yeah. So superconducting qubits are currently one of the most promising qubit systems for quantum computing. There are a lot of options. Superconducting qubits are one of those. And I do a lot of work with superconductors. And in case of superconductors, of course you need the low temperatures just because theyre not superconducting at high temperatures. 

The Conveyor: 

How is Mines preparing engineers for quantum 2.0? 

Meenakshi Singh: 

So one of the things thats different about our program is that there is a big hands-on component. We have a quantum hardware course where we teach them the engineering parts of quantum engineering, like how to run a cryostat, how to use a microwave measurement equipment, things like that in a course versus actually learning them when you join your new job. And then we also have a quantum software course where we teach them public facing quantum computers and how to program them. 

Meenakshi Singh: 

And then we have focused on interdisciplinarity from the start. We really very sincerely do not want this to be a branch of the physics department. So for example, mathematicians and computer scientists and electrical engineers who know a lot about something which is necessary to make quantum technologies work, but who may not have a background in quantum physics to merge their disciplines specific specialty to solve problems in quantum information science. So we are trying to kind of provide them basic background in quantum physics, and they already know a lot of electrical engineering, for example, and they are in a position where they can put those together to make a difference in this field. 

Meenakshi Singh: 

Thanks for listening to The Conveyor. To learn more about how Colorado School of Mines is solving some of the worlds biggest engineering and scientific challenges, visit mines.edu and then join us back here for our next episode. 

This episode of The Conveyor was produced by Ashley Spurgeon and was hosted and edited by Dannon Cox. 

Subscribe

spotify SPOTIFY

Soundcloud SOUNDCLOUD

Apple Podcast APPLE PODCASTS

 

About the Podcast

The Conveyor brings listeners insights into the latest research, new discoveries and world-changing ideas from Colorado School of Mines.

The viewpoints and opinions expressed by featured guests do not necessarily represent those of Colorado School of Mines.