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

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 نشر من قبل Yunbo Zhang
 تاريخ النشر 2000
  مجال البحث فيزياء
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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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