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arXiv · 1210.2367

Spontaneous Conversion from Virtual to Real Photons in the Ultrastrong Coupling Regime

R. Stassi·A. Ridolfo·O. Di Stefano·M. J. Hartmann·S. Savasta
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Abstract

We show that a spontaneous release of virtual photon pairs can occur in a quantum optical system in the ultrastrong coupling regime. In this regime, which is attracting interest both in semiconductor and superconducting systems, the light-matter coupling rate {\Omega}R becomes comparable to the bare resonance frequency of photons {\omega}0. In contrast to the dynamical Casimir effect and other pair creation mechanisms, this phenomenon does not require external forces or time dependent parameters in the Hamiltonian.

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R. Stassi, A. Ridolfo, O. Di Stefano, M. J. Hartmann, S. Savasta. 2012-10-08. Spontaneous Conversion from Virtual to Real Photons in the Ultrastrong Coupling Regime. https://doi.org/10.1103/physrevlett.110.243601

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