Exotic Phases and Their Interfaces in Correlated Many-Particle Systems

Florida State University, Tallahassee FL

Investigators

Abstract

NONTECHNICAL SUMMARY This award supports theoretical research and education on exotic properties of many-particle systems with strong interactions. It is known that strong interactions between particles can stabilize various phases of matter that can be very different from those familiar from daily life, like solid, liquid and gas. Understanding such phases is an important goal of condensed matter physics, which may pave the way to technological applications like quantum computation. The PI and his team will study how to reveal the properties of some new phases by probing the interfaces that separate them. Theoretical results are expected to help guide associated experiments and simulations. The research may also be of interest to other fields of physics, including high-energy and gravitational physics. The research activities supported by this award will introduce graduate students to the frontier of condensed matter physics. Recently the PI has published a new graduate level condensed matter textbook, that reflects the transformative developments of this field in the last few decades. He will continue his work in this direction, including working out a solutions manual for its homework problems. Such work will further facilitate education of students in this field. TECHNICAL SUMMARY This award supports theoretical research on exotic quantum phases of many-particle systems with strong interactions. Some of these phases are of topological nature. A main focus of this project is to investigate physical properties of interfaces separating different topological phases, and their relationship to the topological properties of the individual phases. Examples include interfaces between Abelian and non-Abelian quantum Hall phases, and between different non-Abelian phases at the same filling factor but with different topological order. The PI and his team will study both the static and dynamical properties of such interfaces, and the possibility of phase transitions triggered by quantum fluctuations at the interfaces. Another focus of this project is to characterize typical and atypical excited states using concepts from quantum information theory, including entanglement and Kolmogorov complexity. The goal here is to gain deeper understanding of thermalization in isolated quantum systems. A third focus of the project is to understand supersolidity in quasi-one-dimensional systems, using the coupled-wire approach. The PI and his team will use a combination of theoretical and numerical tools in their studies, including mean-field theory, renormalization group, bosonization, and exact diagonalization. They will also attempt to borrow insights and methodology from other fields, including string theory and black hole physics, in which related issues have been studied extensively. These will provide valuable training opportunities for graduate students, as well as stimulating synergy among different fields. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.