Kinetic and thermodynamic temperatures in quantum systems

Alessio Gagliardi; Alessandro Pecchia; Aldo Di Carlo

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arXiv · 1305.2104

Kinetic and thermodynamic temperatures in quantum systems

Alessio Gagliardi·Alessandro Pecchia·Aldo Di Carlo

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Abstract

In this work we present a formalism to describe non equilibrium conditions in systems with a discretized energy spectrum, such as quantum systems. We develop a formalism based on a combination of Gibbs-Shannon entropy and information thermodynamics that arrives to a generalization of the De-Brujin identity applicable to discrete and non-symmetric distributions. This allows to define the concept of a thermodynamic temperature with a different, albeit complementary meaning to the equilibrium kinetic temperature of a system. The theory is applied to Bosonic and Fermionic cases represented by an harmonic oscillator and a single energy state, respectively. We show that the formalism correctly recovers known results at equilibrium, then we demonstrate an application to a genuine non equilibrium state: a coherent quantum oscillator.

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Alessio Gagliardi, Alessandro Pecchia, Aldo Di Carlo. 2013-05-09. Kinetic and thermodynamic temperatures in quantum systems. https://arxiv.org/abs/1305.2104

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