Quantum fluctuations in atomic Josephson junctions: the role of dimensionality

Abstract

We investigate the role of quantum fluctuations in the dynamics of a bosonic Josephson junction in $D$ spatial dimensions, by using beyond mean-field Gaussian corrections. We derive some key dynamical properties in a systematic way for $D=3,2,1$. In particular, we compute the Josephson frequency in the regime of low population imbalance. We also obtain the critical strength of the macroscopic quantum self-trapping. Our results show that quantum corrections increase the Josephson frequency in spatial dimensions $D=2$ and $D=3$, but they decrease it in the $D=1$ case. The critical strength of macroscopic quantum self-trapping is instead reduced by quantum fluctuations in $D=2$ and $D=3$ cases, while it is enhanced in the $D=1$ configuration. We show that the difference between the cases of D = 2 and D = 3 on one side, and D = 1 on the other, can be related to the qualitatively different dependence of the interaction strength on the scattering length in the different dimensions.

25 pages, 9 figures, 2 tables

References in corpus (4)

• Connecting dissipation and phase slips in a Josephson junction between fermionic superfluids
• The Josephson effect throughout the BCS-BEC crossover
• Finite-size effects in a bosonic Josephson junction
• On-shell approximation for the s-wave scattering theory

Cited by in corpus (3)

• Josephson Dynamics of 2D Bose-Einstein Condensates in Dual-Core Trap: Homogeneous, Droplet-Droplet, and Vortex-Vortex Regimes
• Interaction-induced dissipative quantum phase transition in a head-to-tail atomic Josephson junction
• Low-energy atomic scattering: s-wave relation between the interaction potential and the phase shift