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Driven Macroscopic Quantum Tunneling of Ultracold Atoms in Engineered Optical Lattices

Ramaz Khomeriki·Stefano Ruffo·Sandro Wimberger
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Abstract

Coherent macroscopic tunneling of a Bose-Einstein condensate between two parts of an optical lattice separated by an energy barrier is theoretically investigated. We show that by a pulsewise change of the barrier height, it is possible to switch between tunneling regime and a self-trapped state of the condensate. This property of the system is explained by effectively reducing the dynamics to the nonlinear problem of a particle moving in a double square well potential. The analysis is made for both attractive and repulsive interatomic forces, and it highlights the experimental relevance of our findings.

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Ramaz Khomeriki, Stefano Ruffo, Sandro Wimberger. 2006-09-30. Driven Macroscopic Quantum Tunneling of Ultracold Atoms in Engineered Optical Lattices. https://doi.org/10.1209/0295-5075%2F77%2F40005

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