Finite frequency backscattering current noise at a helical edge

Article

关键词: JETP LETTERS 108;    SHOT-NOISE;    QUANTUM;    TRANSPORT;    CONDUCTION;   

DOI  :  10.1103/PhysRevB.102.125309

来源: SCIE

【 摘 要 】

Magnetic impurities with sufficient anisotropy could account for the observed strong deviation of the edge conductance of 2D topological insulators from the anticipated quantized value. In this work we consider such a helical edge coupled to dilute impurities with an arbitrary spin S and a general form of the exchange matrix. We calculate the backscattering current noise at finite frequencies as a function of the temperature and applied voltage bias. We find that, in addition to the Lorentzian resonance at zero frequency, the backscattering current noise features Fano-type resonances at nonzero frequencies. The widths of the resonances are controlled by the spectrum of corresponding Korringa rates. At a fixed frequency the backscattering current noise has nonmonotonic behavior as a function of the bias voltage.

【 授权许可】

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