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arXiv · 0910.2805

Metastable quantum phase transitions in a periodic one-dimensional Bose gas: II. Many-body theory

R. Kanamoto·L. D. Carr·M. Ueda
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Abstract

We show that quantum solitons in the Lieb-Liniger Hamiltonian are precisely the yrast states. We identify such solutions clearly with Lieb's type II excitations from weak to strong interactions, clarifying a long-standing question of the physical meaning of this excitation branch. We demonstrate that the metastable quantum phase transition previously found in mean field analysis of the weakly-interacting Lieb-Liniger Hamiltonian [Phys. Rev. A {\bf 79}, 063616 (2009)] extends into the medium- to strongly-interacting regime of a periodic one-dimensional Bose gas. Our methods are exact diagonalization, finite-size Bethe ansatz, and the boson-fermion mapping in the Tonks-Girardeau limit.

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R. Kanamoto, L. D. Carr, M. Ueda. 2009-10-15. Metastable quantum phase transitions in a periodic one-dimensional Bose gas: II. Many-body theory. https://doi.org/10.1103/physreva.81.023625; 10.1103/physreva.81.049903

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