2016/05/31 by Lijun Zhu, Changtao Hou, Chandra M. Varma +1
Physics and Astronomy · #Classical XY model #Critical exponent #Criticality #Dissipation #Dissipative system #Exponent #Gravitational singularity #Phase (matter) #Phase diagram #Phase transition #Physics #Physics of Superconductivity and Magnetism #Quantum #Quantum and electron transport phenomena #Quantum many-body systems #Quantum mechanics #Quantum phase transition #Renormalization group #Statistical physics #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.94.235156
published as Phys. Rev. B 94, 235156 (2016) · Improvements in presentation and addition of a section with results for periodic form of dissipation
openalex created_date 2016/06/24 · openalex publication_date 2016/12/28 · arxiv created 2017/01/01 · arxiv updated 2017/01/04 · openalex updated_date 2026/08/06
Earlier Monte Carlo calculations on the dissipative two-dimensional XY model are extended in several directions. We study the phase diagram and the correlation functions when dissipation is very small, where it has properties of the classical 3D-XY transition, i.e., one with a dynamical critical exponent z=1. The transition changes from z=1 to the class of criticality with z\ensuremath→\ensuremath∞ driven by topological defects, discovered earlier, beyond a critical dissipation. We also find that the critical correlations have power-law singularities as a function of tuning the ratio of the kinetic energy to the potential energy for fixed large dissipation, as opposed to essential singularities on tuning dissipation keeping the former fixed. A phase with temporal disorder but spatial order of the Kosterlitz-Thouless form is also further investigated. We also present results for the transition when the allowed Caldeira-Leggett form of dissipation and the allowed form of dissipation coupling to the compact rotor variables are both included. The nature of the transition is then determined by the Caldeira-Leggett form.