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Absence of single particle Bose-Einstein condensation at low densities for bosons with correlated-hopping

Rachel Bendjama·Brijesh Kumar·Frederic Mila
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Abstract

Motivated by the physics of mobile triplets in frustrated quantum magnets, the properties of a two dimensional model of bosons with correlated-hopping are investigated. A mean-field analysis reveals the presence of a pairing phase without single particle Bose-Einstein condensation (BEC) at low densities for sufficiently strong correlated-hopping, and of an Ising quantum phase transition towards a BEC phase at larger density. The physical arguments supporting the mean-field results and their implications for bosonic and quantum spin systems are discussed.

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Rachel Bendjama, Brijesh Kumar, Frederic Mila. 2005-07-01. Absence of single particle Bose-Einstein condensation at low densities for bosons with correlated-hopping. https://doi.org/10.1103/physrevlett.95.110406

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