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Event Overview
Helical edge resistance introduced by charge puddles
Speaker: Leonid Glazman, Yale University
Date & Time: October 11, 2013 16:00 - 17:00
Location: UBC, Hennings 318
Local Contact: Joshua Folk
Intended Audience: Graduate
Electron puddles created by doping of a 2D topological insulator may violate the ideal helical edge conductance. Because of a long electron dwelling time, even a single puddle may lead to a significant inelastic backscattering. We find the resulting correction to the perfect edge conductance. Generalizing to multiple puddles, we assess the dependence of the helical edge resistance on temperature and doping level. Puddles with odd electron number carry a spin and are effective in backscattering in a broad temperature range. That may explain the experimentally found weak temperature dependence of the excess resistance of helical edges.