Sub- to super-Poissonian crossover of current noise in helical edge states coupled to a spin impurity in a magnetic field

@article{Probst2022SubTS,
  title={Sub- to super-Poissonian crossover of current noise in helical edge states coupled to a spin impurity in a magnetic field},
  author={Benedikt Probst and Pauli Virtanen and Patrik Recher},
  journal={Physical Review B},
  year={2022}
}
Edge states of two-dimensional topological insulators are helical and single-particle backscattering is prohibited by time-reversal symmetry. In this work, we show that an isotropic exchange coupling of helical edge states (HES) to a spin 1/2 impurity subjected to a magnetic field results in characteristic backscattering current noise (BCN) as a function of bias voltage and tilt angle between the direction of the magnetic field and the quantization axis of the HES. In particular, we find… 

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