RT Journal Article
T1 Nonequilibrium dynamics of a fast oscillator coupled to Glauber spins
A1 Bonilla, Luis L.
A1 Prados, Antonio
A1 Carpio Rodríguez, Ana María
AB A fast harmonic oscillator is linearly coupled with a system of Ising spins that are in contact with a thermal bath, and evolve under a slow Glauber dynamics at dimensionless temperature theta. The spins have a coupling constant proportional to the oscillator position. The oscillator spin interaction produces a second order phase transition at theta = 1 with the oscillator position as its order parameter: the equilibrium position is zero for theta > 1 and nonzero for theta < 1. For theta < 1, the dynamics of this system is quite different from relaxation to equilibrium. For most initial conditions, the oscillator position performs modulated oscillations about one of the stable equilibrium positions with a long relaxation time. For random initial conditions and a sufficiently large spin system, the unstable zero position of the oscillator is stabilized after a relaxation time proportional to theta. If the spin system is smaller, the situation is the same until the oscillator position is close to zero, then it crosses over to a neighborhood of a stable equilibrium position about which it keeps oscillating for an exponentially long relaxation time. These results of stochastic simulations are predicted by modulation equations obtained from a multiple scale analysis of macroscopic equations.
PB IOP Publishing
SN 1742-5468
YR 2010
FD 2010
LK https://hdl.handle.net/20.500.14352/42112
UL https://hdl.handle.net/20.500.14352/42112
LA eng
NO Bonilla, L. L., Prados, A. y Carpio Rodríguez, A. M. «Nonequilibrium dynamics of a fast oscillator coupled to Glauber spins». Journal of Statistical Mechanics: Theory and Experiment, vol. 2010, n.o 09, septiembre de 2010, p. P09019. DOI.org (Crossref), https://doi.org/10.1088/1742-5468/2010/09/P09019.
NO Ministerio de Ciencia, Innovación y Universidades (España)
DS Docta Complutense
RD 17 abr 2025