Por favor utiliza este link para citar o compartir este documento: http://repositoriodigital.academica.mx/jspui/handle/987654321/86097
Título: Non-equivalence of the microcanonical and canonical ensembles in a bosonic Josephson junction
Palabras clave: Josephson effect
bosonic Josephson junction
quantum ensemble theory
Fecha de publicación: 31-Jul-2012
Editorial: Revista mexicana de física
Descripción: We investigate the thermodynamic properties of a bosonic Josephson junction in the full quantum approach and, in particular, we concentrate in studying the thermal averages of one- and two-body properties below and above the transition from delocalized to self-trapped regimes. This temperature dependence is determined by using the fact that at equilibrium the microcanonical and canonical ensembles should be equivalent. To establish the robustness of the equilibrium state, we first study a one body property and show numerically that any arbitrary state localized in energy, when evolved, reaches a stationary or equilibrium state. Comparison among averages of one- and two-body properties in the microcanonical and canonical ensembles reveals discrepances, thus leading to non-equivalence among these ensembles. Such averages differences can be attributed to the fact that the Hilbert space of the system scales as its size N, and consequently, the entropy does not scale as N. We further find as a natural consequence of studying the finite bosonic Josephson junction in the two-mode Bose Hubbard context, that positive and negative temperatures are obtained. This result can be generalized for any finite optical lattice.
Other Identifiers: http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0035-001X2011000400014
Aparece en las Colecciones:Revista Mexicana de Física

Archivos de este documento:
No hay archivos asociados a este documento.


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.