Spin-spin correlators in the majorana representation.
نویسندگان
چکیده
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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عنوان ژورنال:
- Physical review letters
دوره 91 20 شماره
صفحات -
تاریخ انتشار 2003