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Spin dynamics from Majorana fermions

W. Mao·P. Coleman·C. Hooley·D. Langreth
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Abstract

Using the Majorana fermion representation of spin-1/2 local moments, we show how it is possible to directly read off the dynamic spin correlation and susceptibility from the one-particle propagator of the Majorana fermion. We illustrate our method by applying it to the spin dynamics of a non-equilibrium 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 Curie susceptibility recently found by Parcollet and Hooley [Phys. Rev. B {\bf 66}, 085315 (2002)].

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W. Mao, P. Coleman, C. Hooley, D. Langreth. 2003-09-19. Spin dynamics from Majorana fermions. https://doi.org/10.1103/physrevlett.91.207203

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