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arXiv · 1006.0117

Quantum tunneling time of a Bose-Einstein condensate traversing through a laser-induced potential barrier

Zhenglu Duan·Bixuan Fan·Chun-Hua Yuan·Jing Cheng·Shiyao Zhu·Weiping Zhang
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Abstract

We theoretically study the effect of atomic nonlinearity on the tunneling time in the case of an atomic Bose-Einstein condensate (BEC) traversing the laser-induced potential barrier. The atomic nonlinearity is controlled to appear only in the region of the barrier by employing the Feshbach resonance technique to tune interatomic interaction in the tunneling process. Numerical simulation shows that the atomic nonlinear effect dramatically changes the tunneling behavior of the BEC matter wave packet, and results in the violation of Hartman effect and the occurrence of negative tunneling time.

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Zhenglu Duan, Bixuan Fan, Chun-Hua Yuan, Jing Cheng, Shiyao Zhu, Weiping Zhang. 2010-06-01. Quantum tunneling time of a Bose-Einstein condensate traversing through a laser-induced potential barrier. https://doi.org/10.1103/physreva.81.055602

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