title: Robust helical edge transport in gated InAs/GaSb bilayers.
abstract: We have engineered electron-hole bilayers of inverted InAs/GaSb quantum wells, using dilute silicon impurity doping to suppress residual bulk conductance. We have observed robust helical edge states with wide conductance plateaus precisely quantized to 2e^{2}/h in mesoscopic Hall samples. On the other hand, in larger samples the edge conductance is found to be inversely proportional to the edge length. These characteristics persist in a wide temperature range and show essentially no temperature dependence. The quantized plateaus persist to a 12 T applied in-plane field; the conductance increases from 2e^{2}/h in strong perpendicular fields manifesting chiral edge transport. Our study presents a compelling case for exotic properties of a one-dimensional helical liquid on the edge of InAs/GaSb bilayers.
authors: Department of Physics and Astronomy, Rice University, Houston, Texas 77251-1892, USA.
authors: Lingjie
authors: L
authors: Du
authors: Department of Physics and Astronomy, Rice University, Houston, Texas 77251-1892, USA.|IBM Research-Almaden, San Jose, California 95120, USA.
authors: Ivan
authors: I
authors: Knez
authors: Teledyne Scientific and Imaging, Thousand Oaks, California 91630, USA.
authors: Gerard
authors: G
authors: Sullivan
authors: Department of Physics and Astronomy, Rice University, Houston, Texas 77251-1892, USA.
authors: Rui-Rui
authors: RR
authors: Du