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arXiv · 0906.2640

Trap-size scaling in confined particle systems at quantum transitions

Massimo Campostrini·Ettore Vicari
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Abstract

We develop a trap-size scaling theory for trapped particle systems at quantum transitions. As a theoretical laboratory, we consider a quantum XY chain in an external transverse field acting as a trap for the spinless fermions of its quadratic Hamiltonian representation. We discuss trap-size scaling at the Mott insulator to superfluid transition in the Bose-Hubbard model. We present exact and accurate numerical results for the XY chain and for the low-density Mott transition in the hard-core limit of the one-dimensional Bose-Hubbard model. Our results are relevant for systems of cold atomic gases in optical lattices.

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Massimo Campostrini, Ettore Vicari. 2009-06-15. Trap-size scaling in confined particle systems at quantum transitions. https://doi.org/10.1103/physreva.81.023606

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