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arXiv · 0801.0952

Mott transition in bosonic systems: Insights from the variational approach

Manuela Capello·Federico Becca·Michele Fabrizio·Sandro Sorella
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Abstract

We study the Mott transition occurring for bosonic Hubbard models in one, two, and three spatial dimensions, by means of a variational wave function benchmarked by Green's function Monte Carlo calculations. We show that a very accurate variational wave function, constructed by applying a long-range Jastrow factor to the non-interacting boson ground state, can describe the superfluid-insulator transition in any dimensionality. Moreover, by mapping the quantum averages over such a wave function into the the partition function of a classical model, important insights into the insulating phase are uncovered. Finally, the evidence in favor of anomalous scenarios for the Mott transition in two dimensions are reported whenever additional long-range repulsive interactions are added to the Hamiltonian.

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Manuela Capello, Federico Becca, Michele Fabrizio, Sandro Sorella. 2008-01-07. Mott transition in bosonic systems: Insights from the variational approach. https://doi.org/10.1103/physrevb.77.144517

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