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arXiv · 1406.6833

Quantum phase transitions of atom-molecule Bose mixtures in a double-well potential

Armando Relaño·Jorge Dukelsky·Pedro Perez-Fernandez·Jose M. Arias
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Abstract

The ground state and spectral properties of Bose gases in double-well potentials are studied in two different scenarios: i) an interacting atomic Bose gas, and ii) a mixture of an atomic gas interacting with diatomic molecules. A ground state second-order quantum phase transition (QPT) is observed in both scenarios. For large attractive values of the atom-atom interaction, the ground-state is degenerate. For repulsive and small attractive interaction, the ground-state is not degenerate and is well approximated by a boson coherent state. Both systems depict an excited state quantum phase transition (ESQPT). For the mixed atom-molecule system the critical point of the ESQPT displays a discontinuity in the first derivative of the density of states.

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Armando Relaño, Jorge Dukelsky, Pedro Perez-Fernandez, Jose M. Arias. 2014-10-20. Quantum phase transitions of atom-molecule Bose mixtures in a double-well potential. https://doi.org/10.1103/physreve.90.042139

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