Berry's Phase in the Presence of a Dissipative Medium: Analytical Results
K. M. Fonseca-Romero, A.C. Aguiar Pinto, J. G. Peixoto de Faria +2 more
We consider the well known model of spin 1/2 coupled to a slowly varying magnetic field in the presence of a weak damping represented by a Lindblad-form operator. We show that Berry's geometrical phase remains unaltered by dissipation. A clear and physically appealing interpretation of this dynamics is given in terms of Bloch's vector. Dissipation effects are twofold: a shrinking in the modulus of this vector, which (geometrically) characterizes coherence loss and a time dependent (dissipation related) precession angle. Experimentally accessible effects are calculated.
•Mar 14, 2000•0 citations