Transport via double constrictions in integer and fractional topological insulators
Abstract
We study transport properties of the helical edge states of two-dimensional integer and fractional topological insulators via double constrictions. Such constrictions couple the upper and lower edges of the sample, and can be made and tuned by adding side gates to the system. Using renormalization group and duality mapping, we analyze phase diagrams and transport properties in each of these cases. Most interesting is the case of two constrictions tuned to resonance, where we obtain Kondo behavior, with a tunable Kondo temperature. Moving away from resonance gives the possibility of a metal-insulator transition at some finite detuning. For integer topological insulators, this physics is predicted to occur for realistic interaction strengths and gives a conductance with two temperature scales where the sign of changes; one being related to the Kondo temperature while the other is related to the detuning.
Keywords
Cite
@article{arxiv.1307.0525,
title = {Transport via double constrictions in integer and fractional topological insulators},
author = {Chia-Wei Huang and Sam T. Carr and Dmitri Gutman and Efrat Shimshoni and Alexander D. Mirlin},
journal= {arXiv preprint arXiv:1307.0525},
year = {2013}
}