Ensemble inequivalence in long-range quantum systems

Abstract

Ensemble inequivalence, i.e. the possibility of observing different thermodynamic properties depending on the statistical ensemble which describes the system, is one of the hallmarks of long-range physics, which has been demonstrated in numerous classical systems. Here, an example of ensemble inequivalence of a long-range quantum ferromagnet is presented. While the $T=0$ microcanonical quantum phase-diagram coincides with that of the canonical ensemble, the phase-diagrams of the two ensembles are different at finite temperature. This is in contrast with the common lore of statistical mechanics of systems with short-range interactions where thermodynamic properties are bound to coincide for macroscopic systems described by different ensembles. The consequences of these findings in the context of atomic, molecular and optical (AMO) setups are delineated.

5 pages, 3 figures

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Cited by in corpus (6)

• First- and second-order quantum phase transitions in the long-range unfrustrated antiferromagnetic Ising chain
• Ensemble Inequivalence in Long-Range Quantum Spin Systems
• High-temperature partition functions and classical simulatability of long-range quantum systems
• Slow decay rate of correlations induced by long-range extended Dzyaloshinskii-Moriya interactions
• Temperature and conditions for thermalization after canonical quenches
• Spectral properties and coding transitions of Haar-random quantum codes