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Universal destabilization and slowing of spin transfer functions by a bath of spins

Daniel Burgarth·Sougato Bose
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Abstract

We investigate the effect of a spin bath on the spin transfer functions of a permanently coupled spin system. When each spin is coupled to a seperate environment, the effect on the transfer functions in the first excitation sector is amazingly simple: the group velocity is slowed down by a factor of two, and the fidelity is destabilized by a modulation of |cos Gt|, where G is the mean square coupling to the environment.

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Daniel Burgarth, Sougato Bose. 2006-03-17. Universal destabilization and slowing of spin transfer functions by a bath of spins. https://doi.org/10.1103/physreva.73.062321

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