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Thermodynamic Analogy for Structural Phase Transitions

Pavel Cejnar·Stefan Heinze·Jan Dobes
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Abstract

We investigate the relationship between ground-state (zero-temperature) quantum phase transitions in systems with variable Hamiltonian parameters and classical (temperature-driven) phase transitions in standard thermodynamics. An analogy is found between (i) phase-transitional distributions of the ground-state related branch points of quantum Hamiltonians in the complex parameter plane and (ii) distributions of zeros of classical partition functions in complex temperatures. Our approach properly describes the first- and second-order quantum phase transitions in the interacting boson model and can be generalized to finite temperatures.

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Pavel Cejnar, Stefan Heinze, Jan Dobes. 2005-01-24. Thermodynamic Analogy for Structural Phase Transitions. https://doi.org/10.1063/1.1996885

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