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arXiv · 0811.2353

Process chain approach to high-order perturbation calculus for quantum lattice models

Andre Eckardt
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Abstract

A method based on Rayleigh-Schroedinger perturbation theory is developed that allows to obtain high-order series expansions for ground-state properties of quantum lattice models. The approach is capable of treating both lattice geometries of large spatial dimensionalities d and on-site degrees of freedom with large state space dimensionalities. It has recently been used to accurately compute the zero-temperature phase diagram of the Bose-Hubbard model on a hypercubic lattice, up to arbitrary large filling and for d=2, 3 and greater [Teichmann et al., Phys. Rev. B 79, 100503(R) (2009)].

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Andre Eckardt. 2009-06-29. Process chain approach to high-order perturbation calculus for quantum lattice models. https://doi.org/10.1103/physrevb.79.195131

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