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Coherent radiation from neutral molecules moving above a grating

Alexey Belyanin·Federico Capasso·Vitaly Kocharovsky·Vladimir Kocharovsky
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Abstract

We predict and study the quantum-electrodynamical effect of parametric self-induced excitation of a molecule moving above the dielectric or conducting medium with periodic grating. In this case the radiation reaction force modulates the molecular transition frequency which results in a parametric instability of dipole oscillations even from the level of quantum or thermal fluctuations. The present mechanism of instability of electrically neutral molecules is different from that of the well-known Smith-Purcell and transition radiation in which a moving charge and its oscillating image create an oscillating dipole. We show that parametrically excited molecular bunches can produce an easily detectable coherent radiation flux of up to a microwatt.

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Alexey Belyanin, Federico Capasso, Vitaly Kocharovsky, Vladimir Kocharovsky. 2001-10-10. Coherent radiation from neutral molecules moving above a grating. https://doi.org/10.1103/physrevlett.88.053602

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