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Berry's Phase in the Presence of a Dissipative Medium

K. M. Fonseca Romero·A. C. Aguiar Pinto·M. T. Thomaz
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Abstract

We consider the spin 1/2 model coupled to a slowly varying magnetic field in the presence of a weak damping represented by a Lindblad-form operators. We show that Berry's geometrical phase remains unaltered by the two dissipation mechanism considered. Dissipation effects are twofold: a shrinking in the modulus of the Bloch's vector, which characterizes coherence loss and a time dependent (dissipation related) precession angle. We show that the line broadening of the Fourier transformation of the components of magnetization is only due to the presence of dissipation.

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K. M. Fonseca Romero, A. C. Aguiar Pinto, M. T. Thomaz. 2002-04-01. Berry's Phase in the Presence of a Dissipative Medium. https://doi.org/10.1016/s0378-4371(01)00589-1

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