You are here: Home / Seminars / Seminar Database / Journey to topological surface states in the quantum limit & Rise of ABO2 triangular oxides

Journey to topological surface states in the quantum limit & Rise of ABO2 triangular oxides

Main Content

Professor Seongshik Oh, Rutgers, The State University of New Jersey
26 August 2019 from 3:30 PM to 4:30 PM
339 Davey
Contact Name
Cui-Zu Chang
Add event to calendar

Since the notion of topological insulator (TI) was envisioned about a decade ago, topology has become a new paradigm in condensed matter physics. Realization of topology as a generic property of materials has led to numerous predictions of classical and quantum topological effects. Although most of the classical topological effects, directly resulting from the presence of the spin-momentum-locked topological surface states, were experimentally confirmed soon after the discovery of TIs, topological quantum effects remained elusive. It turns out that defects, especially interfacial defects, have been the main culprit behind this bottleneck. Once these defects were suppressed with various thin film engineering tricks, a series of topological quantum effects such as quantized Faraday/Kerr rotations, quantum Hall effects, topological quantum phase transitions, zeroth Landau level physics etc. started to emerge. In particular, we find that the zeroth Landau level of the topological surface states harbors a new type of insulating phase characterized by a previously unidentified universality class. In the second part of the talk, I will introduce ABO2 triangular oxides as a new playground of emergent physics, while presenting our recent development of PdCoO2 films as a platform for electronic hydrodynamics and other applications. It is notable that both topological insulators and ABO2 oxides share the same crystal symmetry of R3̅m, which hints that there are even more opportunities lying ahead.

Filed under: