Station Q, Microsoft Research, Santa Barbara, California 93106-6105, USA.
Department of Physics and Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, California 91125, USA.
Phys Rev Lett. 2018 Sep 7;121(10):106601. doi: 10.1103/PhysRevLett.121.106601.
Time-reversal symmetry suppresses electron backscattering in a quantum-spin-Hall edge, yielding quantized conductance at zero temperature. Understanding the dominant corrections in finite-temperature experiments remains an unsettled issue. We study a novel mechanism for conductance suppression: backscattering caused by incoherent electromagnetic noise. Specifically, we show that an electric potential fluctuating randomly in time can backscatter electrons inelastically without constraints faced by electron-electron interactions. We quantify noise-induced corrections to the dc conductance in various regimes and propose an experiment to test this scenario.
时间反演对称性抑制了量子自旋霍尔边缘中的电子背散射，从而在零温度下产生了量子电导。理解有限温度实验中的主要修正仍然是一个未解决的问题。我们研究了一种新的电导抑制机制：由非相干电磁噪声引起的背散射。具体来说，我们表明，随时间随机波动的电势可以在没有电子-电子相互作用所面临的约束的情况下非弹性地背散射电子。我们在各种情况下量化了噪声引起的直流电导修正，并提出了一个实验来检验这种情况。
