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arXiv · 1811.12832

Hybrid master equation for calorimetric measurements

Brecht Donvil·Paolo Muratore-Ginanneschi·Jukka P. Pekola
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Abstract

Ongoing experimental activity aims at calorimetric measurements of thermodynamic indicators of quantum integrated systems. We study a model of a driven qubit in contact with a finite-size thermal electron reservoir. The temperature of the reservoir changes due to energy exchanges with the qubit and an infinite-size phonon bath. Under the assumption of weak coupling and weak driving, we model the evolution of the qubit-electron-temperature as a hybrid master equation for the density matrix of the qubit at different temperatures of the calorimeter. We compare the temperature evolution with an earlier treatment of the qubit-electron model, where the dynamics were modelled by a Floquet master equation under the assumption of drive intensity much larger than the qubit-electron coupling squared. We numerically and analytically inquire the predictions of the two mathematical models of dynamics in the weak-drive parametric region. We numerically determine the parametric regions where the two models of dynamics give distinct temperature predictions and those where their predictions match.

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Brecht Donvil, Paolo Muratore-Ginanneschi, Jukka P. Pekola. 2018-11-30. Hybrid master equation for calorimetric measurements. https://doi.org/10.1103/physreva.99.042127

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