MSE Seminar Series
Friday, April 22, 2022 @11am Doherty Hall 2210
Professor Benjamin Hunt,
Carnegie Mellon University
presents
WTe2: A Two-Dimensional Material Platform Like No Other
ABSTRACT:
WTe2 displays an astonishing range of phenomena. In its bulk form, it is a layered semimetal, but can be exfoliated like graphene. In monolayer form, it becomes a two-dimensional topological insulator that can be tuned to a superconductor with an electric field. In the bilayer, it loses the topological character of the monolayer but gains a new property: it becomes a ferroelectric metal. In the bulk, it has been shown to have no less extraordinary properties: a magnetoresistance up to 13,000,000% that does not saturate, the ability to switch spin currents using anti-damping spin-orbit torque in spintronic devices, among many others. Two monolayers can even be twisted: owing to symmetry, twisted bilayer WTe2 may be a unique system for studying physics in one dimension instead of two. In this talk, I will discuss my group’s experiments on atomically-thin WTe2 using transport, capacitance, and scanning tunneling microscopy, as well as some other recent experimental work from the condensed-matter physics group at CMU. I will show how considerations of dimensionality, crystalline symmetry, and the topology of the WTe2 band structure lead to this extraordinary suite of properties.
BIOGRAPHY:
Prof. Hunt is the Falco DeBenedetti Associate Professor of Physics at Carnegie Mellon. He obtained his Ph.D. from Cornell University in 2009 working in the group of J.C. Seamus Davis. He did postdoctoral work with Ray Ashoori at MIT and with Cory Dean and James Hone at Columbia before coming to CMU in 2015. He is also a Courtesy Professor in the Department of Materials Science and Engineering at CMU. He is the recipient of a Kaufman Foundation Early Investigator Award, a Cottrell Award, and the Department of Energy Early Career Award.