Irfan Siddiqi sees a bright future ahead for Berkeley Physics

December 14, 2023

by Alexander Rony

For Irfan Siddiqi, becoming chair of the Department of Physics is about giving back. Since his arrival at UC Berkeley in 2006, Siddiqi has enjoyed the opportunity to teach, write a quantum textbook, and work with stellar graduate students in his lab. Now, he is helping the department plan how to build the “labs of the future” to advance education and research with modern tools.

Globally recognized as an expert in quantum mechanics, Siddiqi specializes in electronic circuits made of superconducting materials that work at ultra-low temperatures within a fraction of absolute zero. His lab produces extremely small circuits — about the size of fifty nanometers, or fifty billionths of a meter — that are critical components in the dilution refrigerators that enable quantum computing. Siddiqi keeps an old, hand-built cryo-refrigerator outside his Quantum Nanoelectronics Laboratory as a reminder of how far the quantum mechanics field has come.

Siddiqi sat down for an interview to share his appreciation and priorities for the physics department.

What is unique about the Department of Physics at Berkeley?

When I think about Berkeley Physics, the phrase that comes to mind is avant-garde. Here, we have a collection of thinkers who are not afraid to go outside of the box, and what’s unique about our department is that, if you have a question about something that’s not in your field, if you walk down two doors, you’ll find an expert in that field. Putting all those ideas together makes us much more the sum than the individual parts that we are.

Berkeley Physics is a powerhouse for understanding how our universe works, from the smallest scales — looking at atoms and the particles within those particles — to thinking about how those pieces fit together with different theories of physics — such as quantum mechanics and general relativity — to form the universe as we know it, including black holes, dark matter, and dark energy.

Others often measure the quality of a department in terms of statistical metrics — how many prizes have the faculty won and so on — and Berkeley Physics excels in all of these categories. We have numerous Nobel Prize winners. Our faculty are thought leaders across many fields of science, driving innovation both within the country and internationally. But really, what makes Berkeley Physics very special is the vibrant community that comes together when we have the synergy between students, postdocs, faculty, and staff all wanting to explore that scientific frontier together. That, in essence, is what makes Berkeley Physics an incubator for innovation.

Irfan Siddiqi, wearing a suit, talks to a classroom of students, faculty, and staff

Irfan Siddiqi opens the fall 2023 semester with a talk to physics students, faculty, and staff.

How has the field of physics changed?

Physics has changed in many ways, from a science that was often done in a small-scale laboratory setting to something that’s done with a lot of collaborators. In my field, we often did experiments with quantum circuits with only a few people in the lab, but as the field has grown, it has become a very large community. People are thinking about how we pool talents from across the globe to build something that is much more complex.

Physics, at its core, is about problem solving. It allows us to look at the world in a very rational, mathematical, and quantitative way and think about how to change the things around us in a dramatic fashion. What we’ve seen physicists do across the board is amazing. There are no boundaries to where problem solving can take us.

Each generation of students has seen a different era in physics, and what’s particularly special about the time in which we live is that fields and disciplines that were traditionally separated are coming together in a very cross-cutting fashion. For example, in the domain of quantum information science and technology, thinking about how to produce devices that will influence our world from materials that have never been used before is tremendously exciting. That involves folks who are thinking about the materials, the theory of these devices, how to design them, and how to engineer them.

Why did you choose to accept the role of department chair?

What we’ve seen physicists do across the board is amazing. There are no boundaries to where problem solving can take us.

Irfan Siddiqi

I’ve taken a lot from this department. I’ve gotten some of the best students and postdocs that one can hope to get. Many of them have now gone on to become professors and leaders in the field. I’ve enjoyed looking at different scientific frontiers. I’ve had the ability to write a textbook now on quantum measurement. I think it’s high time I give something back.

What priorities are important to the department and you, as chair, over the next year?

We’re evolving as a department and a society into a realm where devices explore new rules of physics, and that requires new types of experimental tools. One of the most important things we must invest in going forward is infrastructure for new types of science.

For example, the quantum science that we do now requires us to be able to remove every single particle of light from our experiment so it doesn’t spoil the quantum mechanics and to remove the vibration from every single material so that we don’t have any single atom vibrating. This is both a challenge and a frontier that remains to be explored. So, we’d like to build those labs of the future and pair them with the pedagogical tools that allow students to exchange ideas using the modern techniques available to us in the digital age.

One of the major projects that Berkeley Physics is looking at is called the Physics Atrium Project. At its core, it's a new face to the building and an ability to interact with each other in a way that’s — through its glass doors — both inviting and open.

The Campanile rises above the Physics building.

This is our house, so we have a collective responsibility to think about how to bankroll it, support it, make it go into the next generation, and make it the laboratory for our children.

Irfan Siddiqi

Why should someone give to the Department of Physics?

As a public university, we strive to think about what new programs and innovations will have an impact on a broad cross-section of society. Berkeley Physics is a truly public institution. We are able to bring together the best minds from every corner of the world. That community gives us the freedom to think about new ideas, new topics, and new issues — but, like any other freedom, the flipside of that coin is responsibility. This is our house, so we have a collective responsibility to think about how to bankroll it, support it, make it go into the next generation, and make it the laboratory for our children.

As a professor, you’ve had many researchers come through your labs. What moments make the job feel rewarding to you?

As a professor, I’ve been fortunate to have some of the most talented graduate students, postdocs, and researchers come through my lab. At last count, we have somewhere between nine and 10 of them who are now professors in the field of quantum information science. That’s a great feeling — to look at folks who have come through this lab, taken ideas that were there, and built upon them in their own independent and unique ways.

Moreover, coming together as a lab, we really come together as a family. I remember one particular incident where a lab member came to my shoulder, brushed off a little bit of dust from my collar, and said, “You represent all of us together as a family.” That was a very touching moment where you can see that everyone’s looking out for each other.

Irfan Siddiqi inspects a quantum refrigerator.