Spontaneous Currents in a Bosonic Ring |

D. Makieła and M.M. Maśka
Department of Theoretical Physics, Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland |

Full Text PDF |

Nonequilibrium dynamics of non-interacting bosons in a one-dimensional ring-shaped lattice is studied by means of the kinetic Monte Carlo method. The system is approximated by the classical XY model (the kinetic term is neglected) and then the simulations are performed for the planar classical spins. We study the dynamics that follows a finite-time quench to zero temperature. If the quench is slow enough the system can equilibrate and finally reaches the ground state with uniform: spin alignment. However, we show that if the quench is faster than the relaxation rate, the system can get locked in a current-carrying metastable state characterized by a nonzero winding number. We analyze how the zero-temperature state depends on the quench rate. |

DOI: 10.12693/APhysPolA.130.569 PACS numbers: 03.75.Lm, 03.75.Kk, 64.60.Ht |