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arXiv · 0902.3366

Recoil-induced subradiance in a cold atomic gas

M. M. Cola·D. Bigerni·N. Piovella
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Abstract

Subradiance, i.e. the cooperative inhibition of spontaneous emission by destructive interatomic interference, can be realized in a cold atomic sample confined in a ring cavity and lightened by a two-frequency laser. The atoms, scattering the photons of the two laser fields into the cavity-mode, recoil and change their momentum. Under proper conditions the atomic initial momentum state and the first two momentum recoil states form a three-level degenerate cascade. A stationary subradiant state is obtained after that the scattered photons have left the cavity, leaving the atoms in a coherent superposition of the three collective momentum states. After a semiclassical description of the process, we calculate the quantum subradiant state and its Wigner function. Anti-bunching and quantum correlations between the three atomic modes of the subradiant state are demonstrated.

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M. M. Cola, D. Bigerni, N. Piovella. 2009-02-19. Recoil-induced subradiance in a cold atomic gas. https://doi.org/10.1103/physreva.79.053622

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