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arXiv · 1902.05814

Periodic thermodynamics of the Rabi model with circular polarization for arbitrary spin quantum numbers

Heinz-Jürgen Schmidt·Jürgen Schnack·Martin Holthaus
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Abstract

We consider a spin $s$ subjected to both a static and an orthogonally applied oscillating, circularly polarized magnetic field while being coupled to a heat bath, and analytically determine the quasi\-stationary distribution of its Floquet-state occupation probabilities for arbitrarily strong driving. This distribution is shown to be Boltzmannian with a quasitemperature which is different from the temperature of the bath, and independent of the spin quantum number. We discover a remarkable formal analogy between the quasithermal magnetism of the nonequilibrium steady state of a driven ideal paramagnetic material, and the usual thermal paramagnetism. Nonetheless, the response of such a material to the combined fields is predicted to show several unexpected features, even allowing one to turn a paramagnet into a diamagnet under strong driving. Thus, we argue that experimental measurements of this response may provide key paradigms for the emerging field of periodic thermodynamics.

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Heinz-Jürgen Schmidt, Jürgen Schnack, Martin Holthaus. 2019-02-15. Periodic thermodynamics of the Rabi model with circular polarization for arbitrary spin quantum numbers. https://doi.org/10.1103/physreve.100.042141

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