English

Dissipative effects on quantum glassy systems

Statistical Mechanics 2009-11-07 v1

Abstract

We discuss the behavior of a quantum glassy system coupled to a bath of quantum oscillators. We show that the system localizes in the absence of interactions when coupled to a subOhmic bath. When interactions are switched on localization disappears and the system undergoes a phase transition towards a glassy phase. We show that the position of the critical line separating the disordered and the ordered phases strongly depends on the coupling to the bath. For a given type of bath, the ordered glassy phase is favored by a stronger coupling. Ohmic, subOhmic and superOhmic baths lead to different transition lines. We draw our conclusions from the analysis of the partition function using the replicated imaginary-time formalism and from the study of the real-time dynamics of the coupled system using the Schwinger-Keldysh closed time-path formalism.

Keywords

Cite

@article{arxiv.cond-mat/0110497,
  title  = {Dissipative effects on quantum glassy systems},
  author = {Leticia F. Cugliandolo and Daniel Grempel and Gustavo Lozano and Homero Lozza and Constantino da Silva Santos},
  journal= {arXiv preprint arXiv:cond-mat/0110497},
  year   = {2009}
}

Comments

39 pages, 13 figures, RevTex