Dynamical Phase Transition from Nonequilibrium Dynamics of Dark Solitons

By holographic duality, we identify a novel dynamical phase transition which results from the temperature dependence of non-equilibrium dynamics of dark solitons in a superfluid.For a non-equilibrium superfluid system with an initial density of dark solitons, there exists a critical temperature $T_d$,above which the system relaxes to equilibrium by producing sound waves, while below which it goes through an intermediate phase with a finite density of vortex-antivortex pairs. In particular, as $T_d$ is approached from below, the density of vortex pairs scales as $(T_d-T{)}^{\gamma }$ with the critical exponent $\gamma =1\mathrm{/}2$.