title: Topological Protection from Random Rashba Spin-Orbit Backscattering: Ballistic Transport in a Helical Luttinger Liquid.
abstract: The combination of Rashba spin-orbit coupling and potential disorder induces a random current operator for the edge states of a 2D topological insulator. We prove that charge transport through such an edge is ballistic at any temperature, with or without Luttinger liquid interactions. The solution exploits a mapping to a spin 1/2 in a time-dependent field that preserves the projection along one randomly undulating component (integrable dynamics). Our result is exact and rules out random Rashba backscattering as a source of temperature-dependent transport, absent integrability-breaking terms.
authors.affiliation: Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA.|Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106, USA.
authors.forename: Hong-Yi
authors.initials: HY
authors.lastname: Xie
authors.affiliation: Department of Physics, Zhejiang University, Hangzhou, Zhejiang 310027, China.
authors.forename: Heqiu
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA.
authors.forename: Yang-Zhi
authors.initials: YZ
authors.lastname: Chou
authors.affiliation: Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA.|Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106, USA.|Rice Center for Quantum Materials, Rice University, Houston, Texas 77005, USA.
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Foster