Matthew Grayson
Northwestern University
Quantum Hall effect (QHE) edges are topologically protected chiral surface states that carry current with zero backscattering. They are responsible for the trademark features of the QHE such as plateau in the Hall resistance, as well as lossless current in the longitudinal resistance. The recent discovery of topological insulators and the quantum spin Hall effect will allow analogous phenomena to occur at room temperature and zero external magnetic field. However, the details of the electrostatic structure of these QHE edges have been revealed experimentally only in the last decade, and there exist predictions that the sharpness of the edge potential may even lead to a destruction of the QHE in small samples. This talk surveys the current experimental and theoretical knowledge about quantum Hall effect edges and focuses on how tunneling spectroscopy measurements help illuminate some of the questions about the sharp-edge limit of the quantum Hall effect. Momentum resolved integer QHE edge-tunneling experiments as well as tunneling spectroscopic fractional QHE edge-tunneling experiments are reviewed.
Friday, June 4th at 4:00 PM
Room L211, Technological Institute
Refreshments are served at 3:30 PM
