Interplay between interaction and nonidentical coupling for a Bose–Einstein Condensate in a triple-well potential

• The interplay between interaction and nonidentical coupling gives rive to a “two negatives make a positive” effect.
• In the weak interaction regime, the beating phenomenon is found.
• In the strong interaction region, the collapse and revival sequences can appear instead of the beating sequences.

We investigate the effect of interaction and nonidentical coupling on the tunneling dynamics of a Bose–Einstein Condensate trapped in a triple-well potential. In certain parameter regions, we find a “two negatives make a positive” effect. While interaction or nonidentical coupling by itself can suppress the tunneling between the wells, both together enhance the tunneling. In addition, it is shown that under appropriate conditions, the mean-field dynamics displays beating phenomenon in the weak interaction regime. We present a physical explanation for such beating phenomenon. The effect of quantum fluctuation on the beating structure is also discussed numerically.