Prof. David G. Cory is, as of 2011, a Professor of Chemistry at the University of Waterloo and researcher at the Institute of Quantum Computing. He currently holds a Canada Excellence Research Chair in the field of Quantum Information Processing. He is affiliated with the Perimeter Institute for Theoretical Physics (PI) as a visiting researcher, the Waterloo Institute of Nanotechnology (WIN) as a member, and is the chair of the advisory committee for the Canadian Institute for Advanced Research (among other titles he currently holds). Prior to his current position at the University of Waterloo, Dr. Cory was a Nuclear Engineering Professor at the Massachusetts Institute of Technology (MIT), where he was known for his work on nuclear magnetic resonance processes. He is known for his leading role in experimental quantum physics research and its applications from the medical to the oil industry. For more about his past work and current research, look to the WIN and PI websites for more information.
Can you briefly describe your research and its potential future uses?
We work on making quantum devices and, of course, quantum mechanics is at the foundation of the universe. Everything that we can do at the level that’s uniquely quantum mechanical, we gain advantage over the classical world. We make quantum sensors, quantum actuators, and quantum computers (hopefully!) for which the applications are much broader than people recognize. If we want to image a single molecule, which would be great for drug discovery, quantum sensors are necessary to do that. To build a sensor that is sensitive to one molecular species and to differentiate it from another, quantum mechanics is a great way to do it; some examples include personalized medicine, environmental sensors, or even detection of past radiation events. Almost anywhere you can imagine, whether it’s oil exploration to drug discovery to health to environmental issues, there are places where quantum mechanics can make a difference. If you went into the labs, you would see a lot of different modalities. You will find labs that look very much like physics labs (which are low-temperature labs that operate under strong magnetic fields). In other labs, we use optics as opposed to [other available] labs that resemble materials science ones (where we grow devices, diamond, magnetic thin films). Some labs very much resemble chemistry labs where we grow two dimensional crystals. All of these labs have to come together in order to make quantum devices. Quantum devices are at the foundation of the world; yet, as we wander through the world, we never see something that is quantum. If you want to something to reveal its quantum nature, it takes a lot of new developments in engineering.
What is the one application of quantum mechanics that is the weirdest or that most people would not recognize?
They’re all weird! Anytime you have quantum mechanics operating in the real world, it’s weird. Magnetic resonance imaging is something that many people have experience with but is, fundamentally, a quantum device; right now, there is constant work being done to improve the ability to use this device. A funny thing (that I’m not doing) but one of my former students is doing is that he’s looking at electron spin resonance in fingernails because looking at the electron spin resonance signal in a nail can tell you about past radiation events. They are developing this as a tool so that, in the event that there was a dirty bomb or any other sort of horrible event, you can track it using people’s fingernails to tell you if they were exposed to radiation or not.
How does the approach of scientific research differ between the US and Canada?
Science is international. As we develop our science, we connect to an international community. If we ever advance in our lives, it doesn’t mean anything until we can effectively and broadly share that. Moving here, I didn’t actually change that community; before I came to Waterloo, I was already engaged with people in Canada and now that I’m in Waterloo, I’m still engaged with people in the United States, Europe, China, and Japan. I think that globally, there is no difference. As for locally, there are always strengths that each community has to offer; the Canadian system, perhaps, strives to have a very broad-based research initiative. In coming from MIT, which is a wonderful place with lots of energy, great students, and great colleagues, and then coming here (to Waterloo) which has the same great things, you can see the difference in culture. At the Institute of Quantum Computing, you’re trying to do something collectively and part of the fun of being here is, when I wake up in the morning and come to work, there is a bunch of colleagues that share my passion and that want to do something together in a specific area. In contrast, MIT is, noticeably, a collection of individuals (whereas Waterloo is a collection of groups). Waterloo has, at its foundation, strong undergraduate programs and outreach through the co-op program that connects the university to students across the world at an early age. Waterloo is continuing to build something that, in my opinion, you can’t find anywhere else in the world. It is taking an institute that is strong at co-op and simultaneously uses that foundation to build a research university. At other universities, these activities are often separate. We have students working in labs during their co-op terms or travel to other universities to do research and, subsequently, bring those skills back to Waterloo. It’s a wonderful new exploration to say that we don’t have to choose one or the other, that we can do both well, and that we can do each of these activities because the other one is also here. As you come to a new place, you get to engage broadly with the community and you get to see people bring their vision here (like Feridun’s [Hamdullahpur]) who has been able to share it across the institute).
What do you think University of Waterloo needs improvement in currently as an institution?
I’m not sure I’d keep the word ‘needs improvement’ but I will say that the world changes. The context for how we deliver education and research continues to change; this is certainly true for education which is changing very rapidly at the moment. It’s a good time to rethink and reinvent how we deliver education. As we bring people to the university who are contributing to the excellence in research, it is also important to engage them in the academic program because teaching is a very rewarding thing to do. When you build a community, you want the community to be rewarding and enabling to the individuals. As we’re building our research-intensive university, part of the reward and the enabling is the ability to do great new science through engineering for which the rewards of having it done well are even better. That may be the piece that undergraduates don’t recognize right away; research and, of course, education in the classroom is learning new things. When each activity is done well, one activity can communicate effectively with the other activity and it would be hard to imagine, for me, to be a professor and not to profess.
How do you believe students should learn and why is this?
To teach students effectively, you have to engage them. It helps to believe that what you’re teaching is interesting and to have some passion. You need to share with students that, when they walk out of the class, it’s not enough that they’ve heard new things – they need to know that they can do new things. As I teach, whether it’s here or MIT, one of the challenges is to convince students of their own capabilities. It’s easy for students to not realize how much they can do; therefore, you need to find ways to challenge them so that they can discover for themselves how much they can achieve. You can see, whether it’s a project or a design activity, or even a challenging homework assignment in a course or a being confronted with a problem in co-op, that these are the opportunities that you can learn for yourself that you are, in fact, capable; this is, of course, what I strive for. I put a lot of emphasis on homework and projects and don’t care so much for what happens in a final exam. There is a place for final exams in that it’s necessary to test some aspects of the coursework but does this equate itself to the question of ‘are you capable?’ You don’t want somebody to equate their future success in a field with the ability to write a final exam.
What kind of teaching styles do you use and why do you think it works?
I think, for me, teaching is to make sure that the students develop new skills and knowledge as well as a chance to display it. Students teach each other very effectively, therefore, one thing I like to do is to stop the class and ask the students a question that they’re going to work on together. Spend a few minutes and let them learn from each other. This year, we tried a new method that worked really well; since we’re in the QNC which has boards all over the place, we stopped and said, “Okay, let’s go into the hall and I’ll hand out some really challenging problems. Break yourselves up into groups of four and five, take a board and work through the problem together while I and the TAs are there to help.” Obviously, this is harder than something we’d normally ask them to do. The amount of interaction in the halls, where the students stayed late and really worked to the ends of the problems, really worked well. I was very impressed with the community of students at Waterloo – the interaction the students have and the self-motivated organization when they need to talk about the problem and learn it was great to see. If you want to learn something, you need to test your knowledge and testing your knowledge with a homework assignment or an exam is not very productive. Testing your knowledge by trying to describe what you know to a fellow student and then having them come back and probe you the questions is very effective; the more we can do that, the better.
How would you adapt these methods to a broader course like Calculus?
Quantum mechanics is at the foundation of everything! You can’t get any broader than that!
Granted, but civil and mechanical engineers never touch the subject of Quantum Mechanics.
They should! When I was at MIT, I had PhD students from almost every department in MIT; that included Civil Engineering, of course, Mechanical Engineering, Electrical Engineering, Nuclear Engineering, Physics, Chemistry, Biology, Bioengineering, Health Sciences, and even a student for business school. They all have important things to bring and the same thing will happen here. To answer your question, what happens when you’re teaching Calculus? Again, there needs to be a dialogue that needs to be developed with the students and, of course, a set of skills. Calculus is challenging in that we teach tools without necessarily teaching the concepts or even, what I would call, skills. I would definitely try to find a way to go deeper…
To try to, go towards the way you teach Quantum Mechanics with the sense of collaborating with students and giving practice problems and putting less emphasis on being able to write a final exam.
Absolutely! If I taught Calculus, there would be lots of homework!
With that said, what’s the one thing you struggle with when teaching a course like Quantum Mechanics?
There are a few things that I struggle with. I’m not organized; I can bring a lot of enthusiasm, I hope, but as one is teaching an undergraduate course, it always helps to have more organization and I always struggle with that. Of course, it always shows up in the way I organize things on the board, which is everywhere. I’ll tell you, the best course I ever took was taught by a wonderful, brilliant, kind old man, Les Foldy, who was Oppenheimer’s student; the worst course he would teach was general relativity. He started from the left and worked through all the way to the right and, finally, at the end of the right, he would write the last equation and then, he would say, “This is wrong. It should be this.” He must have made a dozen errors in going from the left to the right – we had a rule in the class: nobody was allowed to correct him because, if you pointed out his mistake, he would stop (and it’s very hard, at the board, to find your own mistake because you don’t have any perspective as you can’t get far enough away) and try to find the mistake. What we would do is, every day after class, we would all go and take over the same coffee shop, everyday, and we would work through the notes ourselves, correcting all the mistakes. At the end, even though it took an extra hour and it’s not the way I aspire to teach, but it was a very effective learning experience.
Would you say that, not necessarily on purpose, you ended up learning better than you would have if you copied the notes blindly?
Absolutely! Remember that learning is an active process, it can’t be done passively and so how ever people get engaged in the process of learning, it’s always good. The engagement that I see here, of students getting together and talking about whether it’s homework or a problem or a lecture or last year’s quiz, is really beneficial. I would go very far out of my way to make sure that those conversations occur. Sometimes, they should, of course, occur with the faculty and TAs but then, if you’re able to convince your fellow students that you know something, then you probably really do know it.
Because the best way to learn is to teach someone else. Given that you’ve mentioned that you like the collective nature of how students learn, a big part of that has to do with the cohort system considering that we see the same people eight hours a day, every day, for five years. There is talk of introducing a system where it is more like the other faculties where you have a certain set of courses that you have to take but can take it whenever you like as opposed to progressing with a class; do you think this would be detrimental?
I haven’t thought of that because I haven’t been a part of that discussion. I find it extraordinary that the students sit there in the same seats and that it’s the faculty that come and go; I know, as a student, I would go crazy. However, I’m amazed at how collegial and well-run the student population is (which is a real strength in the program) and so, I hope that there’s more flexibility within the program but I wouldn’t want to lose the sense of a shared experience which the Nano program has right now.
What’s the best critique you’ve gotten or the one critique you took to heart?
I find that it works when students come to ask something directly after the class. In class, you’ll notice that I try to hit important points twice such that I’ll give a lecture and then, during the next lecture, I’ll compact it with a little bit more organization. The reason why I do that is, from discussions with students, when you see material for the first time, it’s very difficult to figure out how it fits together. You need to have the second look at it after you’ve had a chance to think about it. If students think about it first, then it works well. I used to teach Introductory Electronics at MIT where I would teach an electronics course for non-EE majors (so everyone else at MIT besides electrical engineers). Very much like the Quantum Mechanics course in Nano, the Electronics course had to cover everything in one semester but still be useful. I changed the course from how it was taught; it used to be taught where lectures were given and then there were a bunch of labs at different random times. I changed it so that we built a new lab and, after the lecture, we would all stand up and walk together to the lab (I would be in the lab) and we would spend a couple of hours doing something that would start of as pretty directive to ‘I want you to build something that does this’ so that you had to bring some ideas. We’d go around every lab connected to the lectures and talk to every group of students and find out ‘what did they know’ or ‘what didn’t they know’ or ‘what did work’ or ‘what didn’t work.’ You combine the efficient means of communicating to a group with the local means of ‘let me hear what you know’ (thereby catering to the individual’s needs). I would love to do that with Quantum Mechanics as well (where you’d attach a lab component somehow to every lecture).
How has the Quantum Mechanics course changed since you first taught it?
I can thank you [the 2014 Nano class] for putting in all that work. Based on the first year I taught in the Nano program, we’ve changed the course so that it has a bit more application and more uses of quantum mechanics. I think we’ll continue to do that; the first time I taught it, the comments about ‘what is this good for’ were a little bit too throwaway but now, this is more central to the course. I hope, at some point, as the curriculum for Nano develops, that there will be a second course in senior year where we can teach quantum design and quantum devices as you take the information and apply it in the light of everything you’ve learned as well. It would be fun to put more devices into what’s taught in Nano.
In the interest for Nano students, what analog course is there on campus that you could direct us to that would give us this education or, if there isn’t one, what is something the Nano students can look into in the event that there isn’t an option for this technical elective course in fourth year?
There are good courses in Electrical Engineering [in photonics for those interested] where you can go learn the material. There’s a beautiful structure to photonics and so it’s a nice thing to learn and teach. I would hope we can do something more, that we could say, ‘now if you’re sitting in the quantum world, you can do these things that you can’t do otherwise.’ One of the pieces you want to give students as they’re leaving a program is to put them on a trajectory to developing their own. A key measure, today, of success of an academic program is how effectively you’ve taught ‘lifetime learning.’ Lifetime learning does not mean you take night school; what it means is that you decide that you’re going to go in this direction and you’re going to make a habit of learning. You’re going to be pushing against the frontier and if you want them to push them against the frontier after they leave, it helps them to bring them to the frontier first and that we can do. IQC is well-positioned to bring them to the frontier; the lovely thing is that IQC added a lot of young faculty members and continues to do (so there are great opportunity). In the area of photonics, we’ve just hired Michael Buchin from Stanford who’s an expert in nanophotonics.
To the effect of bringing students to the frontier and promoting lifelong habit of learning, do you think the technical electives bring students up to that point are we still (sort of)…stuck?
No, we’re not stuck! We’re enabled to do anything we like so we should do something good and great. It helps to not speak too broadly and to say, ‘Ah! Where can we make a difference?’ Even for a place that’s as big as the University of Waterloo, you can’t do everything. One of the advice I give to students is that it’s important to take courses for more than just, ‘yes, I have to learn all of these things.’ You also need to look around and say, ‘Oh! I know I can learn this piece; I don’t know why this is necessarily useful but there’s a great professor who’s very enabling of future ideas and I know it will be a wonderful experience.’ To populate your life with wonderful experiences…
Any and regardless of the knowledge you get, it’s all equal. Going off of that, is there somebody in your past that set the tone as to what your career was going to be?
There were many; Les Foldy, who I already mentioned, is probably the top example at Case Western Reserve University (where I went to school). The final physics course in everything was always taught by him as a nice end-all in university.
Was it his teaching style or his enthusiasm?
His enthusiasm, his knowledge…You want somebody who you never to guess, ‘Does this person really know this subject?’ Demonstrably, you want somebody who knows what they’re talking about and is a very practical [hands-on] person. When it came time to doing something, he could do it; you want to build that into the program such that students see, right in front them, that ‘Yes, you can make a difference.’ He was the kind of person who inspired you to say, ‘let’s see what I can do with this or contribute to it’ (rather than the normal nine-to-five and doing something that the person before you has done). I hope that I can bring some of that enthusiasm and share some passion.