Phase-slips and vortex dynamics in Josephson oscillations between Bose-Einstein condensates

M ABAD; M. GUILLEUMAS; R. MAYOL; F. PIAZZA; D. M. JEZEK; A. SMERZI

EUROPHYSICS LETTERS

EPL ASSOCIATION

Lugar: Bologna; Año: 2015 vol. 109 p. 400051 - 400056

0295-5075

  We study the relation between Josephson dynamics and topological excitations in  a dilute Bose-Einstein condensate confined in a double-well trap. We show that the phase slips responsible for the self-trapping regime are created by vortex rings entering and annihilating inside the weak-link region or created at the center of the barrier and expanding outside the system. Large amplitude oscillations just before the onset of self-trapping are also strictly connected with the dynamics of vortex rings at the edges of the inter-well barrier. Our results extend and analyze the dynamics of the vortex-induced phase slippages suggested a few decades ago in relation to the "ac" Josephson effect of superconducting and superuid helium systems.