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Super-Radiance and the Unstable Photon Oscillator

S. Sivasubramanian·A. Widom·Y. N. Srivastava
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Abstract

If the damping of a simple harmonic oscillator from a thermally random force is sufficiently strong, then the oscillator may become unstable. For a photon oscillator (radiatively damped by electric dipole moments), the instability leads to a low temperature Hepp-Lieb-Preparata super-radiant phase transition. The stable oscillator regime is described by the free energy of the conventional Casimir effect. The unstable (strongly damped) oscillator has a free energy corresponding to Dicke super-radiance.

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S. Sivasubramanian, A. Widom, Y. N. Srivastava. 2000-10-01. Super-Radiance and the Unstable Photon Oscillator. https://doi.org/10.1142/s0217979201004423

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