Shenghan Jiang

Shenghan Jiang

“I became a theorist because I enjoy the curiosity that is inherent in investigating when something unexpected happens. As a condensed matter physicist, I am fascinated by both the mathematical beauty and the predictive power of physics. When you read books about physics, you are able to understand things by following the logic of the author, but when you are doing research, you need to discover your own way to understand things and even derive new physics. That’s one of the most interesting parts of research. One thing I enjoy about my work is interpreting things in new ways—in my own way.”

  • Assistant Professor, Kavli Institute of Theoretical Sciences in Beijing

  • IQIM Postdoctoral Scholar Alumnus

Interview

I am a condensed matter theorist, and I work in strongly correlated systems. I am interested in the collective behavior of electrons. In some materials, electrons interact strongly, in which case the single electron picture may fail and what emerges is the collective mode of electrons. Exotic things such as fractionalization may happen. Examples include fractional quantum Hall systems, high temperature superconductors, et al. My focus is on studying models using both analytical and numerical methods to identify exotic behaviors in these strongly correlated models. Quantum materials are described by very complicated models, and we try to find simplified effective models, such as the Hubbard model and the t-J model, which we believe also capture the essential physics of many exotic behaviors of real materials such as high temperature superconductors.

Even though this type of model looks very simple, it is still very, very hard to solve. As a condensed matter physicist, I am fascinated by both the mathematical beauty and the predictive power of physics. I use analytical methods, such as field theory and exact solvable models to solve or guess solutions and to understand the physics behind the correlated models. By using numerical methods, I am trying to predict phases and phase transitions, and I am trying to see if there are exotic behaviors, such as fractionalizations in realistic models.

I became a theorist because I enjoy the curiosity that is inherent in investigating when something unexpected happens…and because I am bad at experiments. My undergraduate studies were in electronics and communication engineering. I took a lot of physics classes, and I found them very interesting, and I decided to switch directions for my graduate work. I pursued a PhD in theoretical physics because it gives me the opportunity to work to understand things in my own way and because the field is really interesting. I just enjoy doing the work. One of the reasons that I work in strongly correlated systems is because the problems are very complicated. First, although we have some methods to “derive” the effective model by fitting experimental data, we don’t know if the Hamiltonian that we have describes this model. It is very, very hard in a strongly correlated system to determine a Hamiltonian for a specific model. Second, even if we know the Hamiltonian, it is still extremely difficult to solve the problem. You can either guess a solution by physical insight, or you should find a simplified model which could capture the essential physics and at the same time would be easier to solve. One of my motivations for doing research is to understand things in my own way. When you read books about physics, you are able to understand things by following the logic of the author. But when you are doing research, you need to discover your own way to understand things and even derive new physics. That’s one of the most interesting parts of research. One of my favorite parts of my work is interpreting things in new ways—in my own way.

I have a four-month-old baby, and I love getting to spend my time outside of work with her and my wife. We spend many afternoons walking together in the Huntington Library where my wife is a visiting scholar. We enjoy hiking and traveling, and our favorite part of California is the Chinese food. I also enjoy jogging. This area is such a great environment for running, and I regularly run half marathon distances for fun.