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arXiv · 1810.10582

Classical and quantum liquids induced by quantum fluctuations

Miguel M. Oliveira·Pedro Ribeiro·Stefan Kirchner
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Abstract

Geometrically frustrated interactions may render classical ground-states macroscopically degenerate. The connection between classical and quantum liquids and how the degeneracy is affected by quantum fluctuations is, however, less well understood. We study a simple model of coupled quantum and classical degrees of freedom, the so-called Falicov-Kimball model, on a triangular lattice and away from half-filling. For weak interactions the phase diagram features a charge disordered state down to zero temperature. We provide compelling evidence that this phase is a liquid and show that it is divided by a crossover line that terminates in a quantum critical point. Our results offer a new vantage point to address how quantum liquids can emerge from their classical counterparts.

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Miguel M. Oliveira, Pedro Ribeiro, Stefan Kirchner. 2019-05-30. Classical and quantum liquids induced by quantum fluctuations. https://doi.org/10.1103/physrevlett.122.197601

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