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arXiv · 2002.00973

Spectral Structure and Many-Body Dynamics of Ultracold Bosons in a Double-Well

Frank Schäfer·Miguel A. Bastarrachea-Magnani·Axel U. J. Lode·Laurent de Forges de Parny·Andreas Buchleitner
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Abstract

We examine the spectral structure and many-body dynamics of two and three repulsively interacting bosons trapped in a one-dimensional double-well, for variable barrier height, inter-particle interaction strength, and initial conditions. By exact diagonalization of the many-particle Hamiltonian, we specifically explore the dynamical behaviour of the particles launched either at the single particle ground state or saddle point energy, in a time-independent potential. We complement these results by a characterisation of the cross-over from diabatic to quasi-adiabatic evolution under finite-time switching of the potential barrier, via the associated time-evolution of a single particle's von Neumann entropy. This is achieved with the help of the multiconfigurational time-dependent Hartree method for indistinguishable particles (\textsc{Mctdh-x}) -- which also allows us to extrapolate our results for increasing particle numbers.

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Frank Schäfer, Miguel A. Bastarrachea-Magnani, Axel U. J. Lode, Laurent de Forges de Parny, Andreas Buchleitner. 2020-02-03. Spectral Structure and Many-Body Dynamics of Ultracold Bosons in a Double-Well. https://doi.org/10.3390/e22040382

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