English

Tunneling of trapped-atom Bose condensates

Other Condensed Matter 2015-06-25 v1 Superconductivity

Abstract

We obtain the dynamics in number and phase difference, for Bose condensates that tunnel between two wells of a double-well atomic trap, using the (nonlinear) Gross-Pitaevskii equation.The dynamical equations are of the canonical form for the two conjugate variables, and the Hamiltonian corresponds to that of a momentum-shortened pendulum, supporting a richer set of tunneling oscillation modes than for a superconductor Josephson junction, that has a fixed-length pendulum as a mechanical model. Novel modes include "inverted pendulum" oscillations with an average angle of \pi; and oscillations about a self-maintained population imbalance that we term "macroscopic quantum self-trapping". Other systems with this phase-number nonlinear dynamics include twocomponent (interconverting) condensates in a single harmonic trap, and He^{3}B superfluids in two containers connected by micropores.

Keywords

Cite

@article{arxiv.cond-mat/0508581,
  title  = {Tunneling of trapped-atom Bose condensates},
  author = {Subodh R. Shenoy},
  journal= {arXiv preprint arXiv:cond-mat/0508581},
  year   = {2015}
}

Comments

This is an overview of some work done with colleagues on the dynamics of tunneling between interacting bosons, with four distinct oscillation modes, understood through a pendulum mechanical analogue. Published in a festschrift a few years ago, it may be of interest, in view of the recent observation of two tunneling modes in double-well Bose-Einstein condensates, by the Heidelberg group of Oberthaler [PRL 95, 010402 (2005)]