arXiv:1910.12489 · AIP conference proceedings
Chaotic and regular dynamics in the three-site Bose-Hubbard model
Anna A. Bychek, Pavel S. Muraev, Dmitrii N. Maksimov, Evgeny N. Bulgakov, Andrey R. Kolovsky
Abstract
We analyze the energy spectrum of the three-site Bose-Hubbard model. It is shown that this spectrum is a mixture of the regular and irregular spectra associated with the regular and chaotic components of the classical Bose-Hubbard model. We find relative volumes of these components by using the pseudoclassical approach. Substituting these values in the Berry-Robnik distribution for the level spacing statistics we obtain good agreement with the numerical data.