Josephson Effect in Trapped Spin-orbit Coupled Bose-Einstein Condensation

Sumaita Sultana, Golam Ali Sekh

Brandon Anderson, Tudor D. Stanescu, Victor M. Galitski

Dan-Wei Zhang, Libin Fu, Z. D. Wang +1 more

We investigate the quantum dynamics of an experimentally realized spin-orbit-coupled Bose-Einstein condensate in a double-well potential. The spin-orbit coupling can significantly enhance the atomic interwell tunneling. We find the coexistence of internal and external Josephson effects in the system, which are moreover inherently coupled in a complicated form even in the absence of interatomic interactions. Moreover, we show that the spin-dependent tunneling between two wells can induce a net atomic spin current referred as spin Josephson effects. Such spin Josephson effects can be observable under realistic conditions.

Sumaita Sultana, Golam Ali Sekh

Abstract We consider matter-wave bright solitons in helicoidal spin-orbit coupled Bose–Einstein condensates in optical lattices with a view to study Josephson-type oscillation and self-trapping of population imbalance between two pseudo-spin states. For fixed values of nonlinear interaction and lattice parameters, the population imbalance executes Josephson-type oscillation and the frequency of oscillation decreases with the increase of helicoidal gauge potential. The frequency of oscillation, however, increases in presence of nonlinear optical lattices. We find that the population imbalance can oscillate about a non-zero value and result self-trapping for proper choices of parameters of the system. The self-trapping can be enhanced by the increase of helicoidal gauge potential and by properly tuning the lattice parameters.

Jie Wang, Jun-Cheng Liang, Zi-Fa Yu +3 more

Alexander L. Fetter