Hoi Kwan (Kero) Lau 劉愷堃

  • Fellowship in 2014 at University of Ulm

Kero completed both his BSc and MPhil degrees at The Chinese University of Hong Kong. In 2009, he moved to pursue his PhD at the University of Toronto. Aiming to unveil the mystery of our nature as well as to improve the living of human beings, Kero chose theoretical quantum optics and quantum information as his fields of research.

After graduating in 2014, Kero was awarded the Croucher Postdoctoral Fellowship to continue his quest for practical quantum technology at Ulm University, Germany. After the Fellowship ends, Kero briefly worked at Max Planck Institute for the Physics of Complex Systems, before joining the Pritzker School of Molecular Engineering, University of Chicago as a postdoc in 2017.

Starting from September 2020, Kero becomes an assistant professor at Simon Fraser University, Canada. His research aims to solve the current practicality issues of quantum technology by harnessing the advantages of bosonic systems. His work will likely be facilitated by the freedom of Canada, friendliness of Canadians, and fragrance of Tim Hortons coffee.

Research Q&A

Q1: Why should we care about quantum technology?

First of all, quantum technology is at least as powerful as the current classical technology. With quantum superposition available, quantum devices must be able to do more. In fact, we now have concrete evidences that quantum properties can help in secure communication, computation, sensing, and many more. However, quantum technology is not as magic as in sci-fi, it has some fundamental limitations that are placed by physics. Understanding the boundaries of what quantum can and cannot do should be both interesting and useful for human beings.

Q2: Why should we care about bosons?

Why not? Boson is everywhere! Light, microwave, mechanical oscillation, a bunch of spin or atom, ... all of these are effectively bosons. Apart from that, usually bosonic systems can store more quantum information; some of them can be easily scaled up, and can store information for a long time without decay. There are lots of advantages. One just need people to think more carefully how to build/use the devices, so the physical advantages can be converted to practical benefits.

Q3: What exactly does your research do?

Basically I study three things: Physics, Information Theory, and how to bring these two together. For physics, our aim is always building better and better quantum devices. As a theorist, I would try to understand the problems of the current imperfect quantum systems, and suggest new strategies to get rid of the problems.

For information theory, we assume if a perfect quantum device is built someday, what could we do with that. We would hope quantum mechanics can make its performance better than the devices nowadays, but the meaning of "better" is usually very subtle. That's why we need to think about that more carefully.

Perhaps the most interesting part is to bring physics and information together. If we have a crappy bosonic device, can it still be useful? If we want the device to do a task, what bosonic quantum wave function should we pick? There are many interesting and rewarding questions on the boundaries of physics and information theory.

Q4: What have you done?

The field is kind of big and inter-disciplinary. In the past 10 years I took the liberty to taste different flavors of the field. For physics, I studied trapped ions, light, microwave, defect center, spin ensemble, cold atoms, mechanical oscillators. For applications, I studied secure communication, computation, simulation, sensing. My theoretical research generally follows a few similar steps: ask a question, think about that carefully, write down a model to describe the idea, verify it by simple calculations.

Although the field has been developing pretty well recently, it is not uncommon to find simple problems that haven't been understood clearly, and some perceptions that are not always true. For examples, people thought quantum computer has to run at zero temperature, but we found high temperature system can do the same job. People thought perfect transfer of quantum state requires a correct form of interaction, we found that it can be done with any interaction. People attempted to build an accurate sensor by making it lossy, oh well, but there is always noise that makes thing worse... There are always interesting questions that need some minds to think more!

You can learn more about my research from my publications.

Q5: Are you taking students? Can I just drop a message to ask random quantum things?

Yes! I am taking PhD/Master/undergraduate/summer exchange students. Feel free to send me a email if you are interested to work with me. Of course, you are also very welcome if you just want to chat with someone on quantum stuff.

Q6: As a Croucher Fellow, why don't you contribute to Hong Kong?

As a Croucher Fellow, I actually advised the Chief Executive to invest in quantum technology due to its potential and importance. Well, we all know how "visionary" the government is...