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Modified dynamics of weakly coupled BEC's Josephson Junction (BJJ)

Yu-ping Huang·Zhen-sheng Yuan·Lin-fan Zhu·Lin-jiao Luo·Xiao-jing Liu·Ke-zun Xu
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Abstract

The tunnelling quantum dynamics of bimodal BJJ system is modified through introducing an equilibrium condition, which is based on the assumption that the BJJ is tend to keep on its ground state (with a lowest energy) during the oscillation. The tunnelling dynamics of BJJ with symmetric and asymmetric traps is discussed through numerically solving the modified equations. Stationary states are found to exist in the both BJJs. Compared to previous works, the macroscopic quantum self trapping (MQST) is auto-avoided. Meanwhile, it is revealed that the BJJ oscillates with its inherent frequency which is only related to the Josephson energy, which has been testified experimentally in other contexts.

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Yu-ping Huang, Zhen-sheng Yuan, Lin-fan Zhu, Lin-jiao Luo, Xiao-jing Liu, Ke-zun Xu. 2003-09-01. Modified dynamics of weakly coupled BEC's Josephson Junction (BJJ). https://arxiv.org/abs/cond-mat/0309009

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