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arXiv · 2306.04989

Effects of quantum fluctuations on macroscopic quantum tunneling and self-trapping of BEC in a double well trap

Fatkhulla Kh. Abdullaev·Ravil M. Galimzyanov·Akbar M. Shermakhmatov
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Abstract

We study the influence of quantum fluctuations on the macroscopic quantum tunneling and self-trapping of a two-component Bose-Einstein condensate in a double-well trap. Quantum fluctuations are described by the Lee-Huang-Yang term in the modified Gross-Pitaevskii equation. Employing the modified Gross-Pitaevskii equation in scalar approximation, we derive the dimer model using a two-mode approximation. The frequencies of Josephson oscillations and self-trapping conditions under quantum fluctuations are found analytically and proven by numerical simulations of the modified Gross-Pitaevskii equation. The tunneling and localization phenomena are investigated also for the case of the Lee-Huang-Yang fluid loaded in the double-well potential.

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Fatkhulla Kh. Abdullaev, Ravil M. Galimzyanov, Akbar M. Shermakhmatov. 2023-06-08. Effects of quantum fluctuations on macroscopic quantum tunneling and self-trapping of BEC in a double well trap. https://doi.org/10.1088/1361-6455%2Face66d

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