Nonlinear Ballistic Response of Quantum Spin Hall Edge States
Pankaj Bhalla, Ming-Xun Deng, Rui-Qiang Wang, Lan Wang, Dimitrie Culcer
Abstract
Topological edge states (TES) exhibit dissipationless transport, yet their dispersion has never been probed. Here we show that the nonlinear electrical response of ballistic TES ascertains the presence of symmetry breaking terms, such as deviations from nonlinearity and tilted spin quantization axes. The nonlinear response stems from discontinuities in the band occupation on either side of a Zeeman gap, and its direction is set by the spin orientation with respect to the Zeeman field. We determine the edge dispersion for several classes of TES and discuss experimental measurement.
Topics & Concepts
PhysicsZeeman effectCondensed matter physicsNonlinear systemQuantization (signal processing)Spin (aerodynamics)Quantum mechanicsBallistic conductionClassification of discontinuitiesSymmetry (geometry)QuantumDispersion (optics)Symmetry breakingEnhanced Data Rates for GSM EvolutionOrientation (vector space)Spin waveQuantum Hall effectGapless playbackTopological Materials and PhenomenaQuantum and electron transport phenomenaChemical and Physical Properties of Materials