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arXiv · 1111.1988

Defining the effective temperature of a quantum driven system from current-current correlation functions

Alvaro Caso·Liliana Arrachea·Gustavo S. Lozano
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Abstract

We calculate current-current correlation functions and find an expression for the zero-frequency noise of multiterminal systems driven by harmonically time-dependent voltages within the Keldysh non-equilibrium Green's functions formalism. We also propose a fluctuation-dissipation relation for current-current correlation functions to define an effective temperature. We discuss the behavior of this temperature and compare it with the local temperature determined by a thermometer and with the effective temperature defined from a single-particle fluctuation-dissipation relation. We show that for low frequencies all the definitions of the temperature coincide.

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Alvaro Caso, Liliana Arrachea, Gustavo S. Lozano. 2011-11-08. Defining the effective temperature of a quantum driven system from current-current correlation functions. https://doi.org/10.1140/epjb/e2012-30303-0

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