2 research outputs found
Dissipative effects on quantum glassy systems
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.Comment: 39 pages, 13 figures, RevTe