title: Spin decoherence due to fluctuating fields.
abstract: The dynamics of a spin in the presence of a deterministic and a fluctuating magnetic field is solved for analytically to obtain the averaged value of the spin as a function of time for various kinds of fluctuations (noise). Specifically, analytic results are obtained for the time dependence of the expectation value of the spin, averaged over fluctuations, for Gaussian white noise, Gaussian colored noise, and non-Gaussian telegraph noise. Fluctuations cause the decay of the average spin vector (decoherence). For noise with a finite temporal correlation time, a deterministic component of the field can suppress the decoherence of the spin component along the field. Hence, decoherence can be manipulated by controlling the deterministic magnetic field. A simple universal physical picture emerges which explains the mechanism for the suppression of decay.
authors.affiliation: Institute of Theoretical Physics, University of Warsaw, ul. Hoża 69, PL-00-681 Warszawa, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Szańkowski
authors.forename: M
authors.initials: M
authors.lastname: Trippenbach
authors.forename: Y B
authors.initials: YB
authors.lastname: Band
mesh_terms: D003198:Computer Simulation; D004574:Electromagnetic Fields; D015233:Models, Statistical; D016011:Normal Distribution; D013113:Spin Labels
chemical_list: D013113:Spin Labels