Flavortronics in 2D Materials

Time: Friday, February 15, 2019 - 3:00pm - 4:00pm
Type: Seminar Series
Presenter: Fan Zhang; Department of Physics, University of Texas at Dallas
Room/Office: Room 107
J. Robert Mann, Jr. Engineering Student Center
10 Hillhouse Avenue
New Haven, CT 06511
United States

Yale Electrical Engineering Seminar

Fan Zhang, Ph.D.
Department of Physics
University of Texas at Dallas

Flavortronics in 2D Materials

Abstract: Transition metal dichalcogenides (TMDs) provide a unique 2D material platform for discovering novel physics. First, I will introduce the original picture of massive Dirac fermions in the K valleys of monolayer TMDs (as ideal extensions of graphene) and its confirmation by optical spectroscopy, quantum transport, and local compressibility measurements. Unexpectedly, our recent theories and experiments have discovered unconventional Gamma-valley holes and Q- valley electrons in few-layer TMDs. Next, I will focus on elucidating that the TMD Q valleys offer an unprecedented opportunity to realize the solid-state version of flavor symmetry that is fundamental to the quark model but rare in electron systems, in addition to the charge, spin, and valley degrees of freedom. In the quantum Hall regime, we have predicted that the spontaneous flavor symmetry breaking yields ferroelectric valley nematics tunable by an in-plane electric field. In the quantum dot geometry, we have predicted flavor enforced irrational Coulomb peaks and fractional Kondo peaks. These remarkable phenomena lead to a new concept–flavortronics.

Bio: Fan Zhang got his PhD in Physics in 2011 from University of Texas at Austin, where he made original contributions to predicting and elucidating the electrons' interacting and topological properties in graphene few-layers. Then, he spent 3 years as a postdoc at University of Pennsylvania, where he made pioneering contributions to the theory of interfacial electronic states in topological insulators and topological superconductors. Since 2014, he has become an assistant professor of Physics at The University of Texas at Dallas, where he focuses on the study of 2D materials, topological matters, and correlated electrons.

Host: Fengnian Xia (Electrical Engineering)

Friday – February 15, 2019
3:00 to 4:00 pm
Mann Engineering Student Center, 10 Hillhouse Avenue