Model glasses coupled to two different heat baths

Citation
Ae. Allahverdyan et al., Model glasses coupled to two different heat baths, EUR PHY J B, 16(2), 2000, pp. 317-335
Citations number
61
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
EUROPEAN PHYSICAL JOURNAL B
ISSN journal
14346028 → ACNP
Volume
16
Issue
2
Year of publication
2000
Pages
317 - 335
Database
ISI
SICI code
1434-6028(200007)16:2<317:MGCTTD>2.0.ZU;2-H
Abstract
In a p-spin interaction spherical spin-glass model both the spins and the c ouplings are allowed to change with time. The spins are coupled to a heat b ath with temperature T, while the coupling constants are coupled to a bath having temperature T-J. In an adiabatic limit (where relaxation time of the couplings is much larger that of the spins) we construct a generalized two -temperature thermodynamics. It involves entropies of the spins and the cou pling constants. The application for spin-glass systems leads to a standard replica theory with a non-vanishing number of replicas, n = T/T-J. For p > 2 there occur at low temperatures two different glassy phases, depending o n the value of n. The obtained first-order transitions have positive latent heat, and positive discontinuity of the total entropy. This is an essentia lly non-equilibrium effect. The dynamical phase transition exists only for n < 1. For p 2 correlation of the disorder (leading to a non-zero n) remove s the known marginal stability of the spin glass phase. If the observation time is very large there occurs no finite-temperature spin glass phase. In this case there are analogies with the non-equilibrium (aging) dynamics. A generalized fluctuation-dissipation relation is derived.