Crossover in the dynamical critical exponent of a quenched two-dimensional Bose gas

Abstract

We study the phase ordering dynamics of a uniform Bose gas in two dimensions following a quench into the ordered phase. We explore the crossover between dissipative and conservative evolution by performing numerical simulations within the classical field methodology. Regardless of the dissipation strength, we find clear evidence for universal scaling, with dynamical critical exponent $z$ characterising the growth of the correlation length. In the dissipative limit we find growth consistent with the logarithmically corrected law $[t/\log (t/t_0){]}^{1/z}$, and exponent $z=2$, in agreement with previous studies. Decreasing the dissipation towards the conservative limit, we find strong numerical evidence for the expected growth law $t^{1/z}$. However, we observe a smooth crossover in $z$ that converges to an anomalous value distinctly lower than $2$ at a small finite dissipation strength. We show that this lower exponent may be attributable to a power-law vortex mobility arising from vortex--sound interactions.

12 pages, 13 figures. Content the same as published version

References in corpus (14)

• Spontaneous vortices in the formation of Bose-Einstein condensates
• Dynamics and statistical mechanics of ultra-cold Bose gases using c-field techniques
• Critical Dynamics of Spontaneous Symmetry Breaking in a Homogeneous Bose gas
• Emergence of coherence in a uniform quasi-two-dimensional Bose gas
• Non-thermal fixed points: effective weak-coupling for strongly correlated systems far from equilibrium
• Emergence of a Turbulent Cascade in a Quantum Gas
• XMDS2: Fast, scalable simulation of coupled stochastic partial differential equations
• Emergence of order from turbulence in an isolated planar superfluid
• Nonthermal fixed points and the functional renormalization group
• Bose-Einstein Condensation from a Rotating Thermal Cloud: Vortex Nucleation and Lattice Formation
• Bidirectional dynamic scaling in an isolated Bose gas far from equilibrium
• Spectral energy transport in two-dimensional quantum vortex dynamics
• Phase ordering kinetics of a nonequilibrium exciton-polariton condensate
• Crossover in the dynamical critical exponent of a quenched two-dimensional Bose gas

Cited by in corpus (10)

• Universal Scaling of the Dynamic BKT Transition in Quenched 2D Bose Gases
• Crossover in the dynamical critical exponent of a quenched two-dimensional Bose gas
• Universal Coarsening in a Homogeneous Two-Dimensional Bose Gas
• A universal speed limit for spreading of coherence
• Kelvin waves in nonequilibrium universal dynamics of relativistic scalar field theories
• Comparison of the microcanonical population annealing algorithm with the Wang-Landau algorithm
• Stochastic Gross-Pitaevskii theory for a spin-1 Bose gas: Application to superfluidity in two dimensions
• Equilibrium, Relaxation and Fluctuations in homogeneous Bose-Einstein Condensates: Linearized Classical Field Analysis
• Anomalous non-thermal fixed point in a quasi-two-dimensional dipolar Bose gas
• Decaying superfluid turbulence near an anomalous non-thermal fixed point