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arXiv · 1105.2418

Strong coupling expansion for the Bose-Hubbard and the Jaynes-Cummings lattice model

Christoph Heil·Wolfgang von der Linden
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Abstract

A strong coupling expansion, based on the Kato-Bloch perturbation theory, which has recently been proposed by Eckardt et al. [Phys. Rev. B 79, 195131] and Teichmann et al. [Phys. Rev. B 79, 224515] is implemented in order to study various aspects of the Bose-Hubbard and the Jaynes-Cummings lattice model. The approach, which allows to generate numerically all diagrams up to a desired order in the interaction strength is generalized for disordered systems and for the Jaynes-Cummings lattice model. Results for the Bose-Hubbard and the Jaynes-Cummings lattice model will be presented and compared with results from VCA and DMRG. Our focus will be on the Mott insulator to superfluid transition.

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Christoph Heil, Wolfgang von der Linden. 2012-07-26. Strong coupling expansion for the Bose-Hubbard and the Jaynes-Cummings lattice model. https://doi.org/10.1088/0953-8984%2F24%2F29%2F295601

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