Oka Group

The Institute for Solid State Physics, The University of Tokyo

For students

You are greatly welcomed. If you are interested in research opportunities in our group, please contact Oka. Visiting the laboratory before the graduate school application is highly recommended.

You are greatly welcomed. If you are interested in research opportunities in our group, please contact Oka.

For details about an entrance exam, please look at Graduate Admissions.

Q&A

Here we answer questions frequently asked during lab visits.

Q1. Do people come to the lab every day?

A1. Most members do come regularly (unless they have special circumstances such as business trips). There is basically no mandatory core time.

Q2. What kind of activities does the lab have?

A2. We hold regular lab meetings. In addition, reading groups and seminars are organized voluntarily by members. Theory seminars and other events are also held within ISSP, providing opportunities to hear about research from a wide range of researchers.

Q3. Is it okay if I come from a different university?

A3. As long as you have a basic knowledge of physics and mathematics, there is no problem at all. We welcome people from diverse backgrounds.

Q4. What is the employment situation like?

A4. Since the lab was only established in 2021, no one has gone through the job-hunting process yet, so we cannot say for certain. In general, most students proceed to the doctoral program after obtaining their master's degree.

Q5. What kind of studying should I do as an undergraduate?

A5. We recommend working through core textbooks on condensed matter theory and field theory hands-on and at your own pace. The following textbooks, in particular, form a common language in our group. You do not need to master all of them, but we hope you have the determination to tackle these books and work through the problems.

Condensed matter theory / Many-body problems:

Quantum field theory:

It is also beneficial to study interdisciplinary areas according to your interests. Statistical mechanics, in particular, is a foundation of physics, and deepening your understanding of it is always worthwhile. In recent years, ideas from (quantum) information theory and geometry have been increasingly incorporated into condensed matter theory. Although the following references are somewhat advanced, they are also recommended.

Topological phases:

Our group also conducts research on nonequilibrium quantum systems and biological systems. Below are some references that can serve as starting points.

Q6. About research themes

A6. Research themes often emerge from chance, luck, or casual conversations. Sometimes a paper read during one's student days takes shape over many years. In fact, Oka's paper on Floquet states [PhysRevB.79.081406] was born out of the process of trying to understand Schwinger 1951 [PhysRev.82.664], which he read as a student. Schwinger 1951 re-derives the electric-field-induced polarization in QED from the "energy" (Heisenberg–Euler effective action). Extending this to AC electric fields, the "energy" becomes the Floquet quasi-energy. Today, quasi-energies are measured using time-resolved ARPES, and what is being directly measured there are quantum geometric quantities arising from nonadiabatic processes.

Q7. About research themes (continued)

A7. In quantum physics, there are fields dealing with exotic phenomena emerging from many-body degrees of freedom in quantum materials (such as superconductivity and the fractional quantum Hall effect), as well as fields like quantum optics that focus on quantum measurement and quantum control. AMO (atomic, molecular, and optical) physics, including ultracold atomic systems, and quantum information science provide innovative platforms that integrate these areas. In biological systems, there are also open quantum systems that exploit fluctuations and reaction networks. We expect that feeding back the achievements of these interdisciplinary fields into quantum materials research will lead to new insights.