Spin-spin correlators in Majorana representation

Alexander Shnirman; Yuriy Makhlin

doi:10.1103/physrevlett.91.207204

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Spin-spin correlators in Majorana representation

Alexander Shnirman·Yuriy Makhlin

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Abstract

In the Majorana representation of a spin 1/2 we find an identity which relates spin-spin correlators to one-particle fermionic correlators. This should be contrasted with the straightforward approach in which two-particle (four-fermion) correlators need to be calculated. We discuss applications to the analysis of the dynamics of a spin coupled to a dissipative environment and of a quantum detector performing a continuous measurement of a qubit's state.

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Alexander Shnirman, Yuriy Makhlin. 2003-05-04. Spin-spin correlators in Majorana representation. https://doi.org/10.1103/physrevlett.91.207204

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