title: Pulse-noise approach for classical spin systems.
abstract: For systems of classical spins interacting with the bath via damping and thermal noise, an approach is suggested to replace the white noise by a pulse noise acting at regular time intervals Δt, within which the system evolves conservatively. The method is working well in the typical case of a small dimensionless damping constant λ and allows a considerable speedup of computations by using high-order numerical integrators with a large time step δt (up to a fraction of the precession period), while keeping δt≪Δt to reduce the relative contribution of noise-related operations. In cases when precession can be discarded, δt can be increased up to a fraction of the relaxation time ∝1/λ that leads to a further speedup. This makes equilibration speed comparable with that of the Metropolis Monte Carlo method. The pulse-noise approach is tested on single-spin and multispin models.
authors.affiliation: Physics Department, Lehman College and Graduate School, The City University of New York, 250 Bedford Park Boulevard West, Bronx, New York 10468-1589, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Garanin