title: Berry phase for a spin 1/2 particle in a classical fluctuating field.
abstract: The effect of fluctuations in the classical control parameters on the Berry phase of a spin 1/2 interacting with an adiabatically cyclically varying magnetic field is analyzed. It is explicitly shown that in the adiabatic limit dephasing is due to fluctuations of the dynamical phase.
authors.affiliation: NEST-INFM & Scuola Normale Superiore, piazza dei Cavalieri 7, I-56126 Pisa, Italy.
authors.forename: Gabriele
authors.initials: G
authors.lastname: De Chiara
authors.forename: G Massimo
authors.initials: GM
authors.lastname: Palma