Nonlinear tunneling and chaos between two Bose–Einstein condensates trapped in time-dependent potential

Abstract

In this Letter, we discuss the macroscopic quantum self-trapping (MQST) and coherent atomic tunneling between two weakly coupled Bose–Einstein condensates confined in a time-dependent double-well trap. It is shown that the nonlinear interaction and the time-periodic external field can dramatically affect the MQST, lead to the high-order Bloch harmonics of the population imbalance, and periodic or chaotic behavior. We give out the onset point of chaos by Lyapunov exponent and the phase plots. It is found that the sudden change on the quasi-energy corresponds to the transition from libration to rotation.