A new expansion around mean field for the quantum Ising model
| dc.creator | De Pasquale, F. | |
| dc.creator | Giampaolo, S. M. | |
| dc.date | 2002-01-28 | |
| dc.date.accessioned | 2026-07-07T02:44:16Z | |
| dc.date.available | 2026-07-07T02:44:16Z | |
| dc.description | We show that an high temperature expansion at fixed order parameter can be derived for the quantum Ising model. The basic point is to consider a statistical generating functional associated to the local spin state. The probability at thermal equilibrium of this state reflects directly the occurrence of a spontaneous symmetry breaking. It is possible to recover the expansion around the mean field in the system dimensionality if the ``direction'' in the Hilbert space of local spin states is suitably chosen. Results for the free energy at the critical temperature, as a function of the transverse field, in first order approximation in the inverse system dimensionality are compared with those of the standard approach. | |
| dc.description | 10 Pages + 2 Figs. Submitted to Prl | |
| dc.identifier | https://arxiv.org/abs/cond-mat/0201505 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/0201505 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/18847 | |
| dc.subject | Statistical Mechanics | |
| dc.title | A new expansion around mean field for the quantum Ising model | |
| dc.type | text |