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Periodic instanton method and macroscopic quantum tunneling between two weakly-linked Bose-Einstein condensates

Yunbo Zhang·H. J. W. Müller-Kirsten
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Abstract

A new method is used to investigate the tunneling between two weakly-linked Bose-Einstein condensates confined in double-well potential traps. The nonlinear interaction between the atoms in each well contributes to a finite chemical potential, which, with consideration of periodic instantons, leads to a remarkably high tunneling frequency. This result can be used to interpret the newly found Macroscopic Quantum Self Trapping (MQST) effect. Also a new kind of first-order crossover between different regions is predicted.

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Yunbo Zhang, H. J. W. Müller-Kirsten. 2001-05-09. Periodic instanton method and macroscopic quantum tunneling between two weakly-linked Bose-Einstein condensates. https://doi.org/10.1103/physreva.64.023608

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