Spin dynamics from majorana fermions.

  title={Spin dynamics from majorana fermions.},
  author={W. Mao and Piers Coleman and Chris A. Hooley and David C. Langreth},
  journal={Physical review letters},
  volume={91 20},
Using the Majorana fermion representation of spin-1/2 local moments, we show how the dynamic spin correlation and susceptibility are obtained directly from the one-particle Majorana propagator. We illustrate our method by applying it to the spin dynamics of a nonequilibrium quantum dot, computing the voltage-dependent spin relaxation rate and showing that, at weak coupling, the fluctuation-dissipation relation for the spin of a quantum dot is voltage dependent. We confirm the voltage-dependent… 

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