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arXiv · 0712.2956

Twin stimulated amplification of light and matter waves in an atom-photon pair laser

Thomas Salzburger·Helmut Ritsch
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Abstract

We consider ultracold atoms in a far detuned optical lattice orientated across a high-Q optical resonator. Applying an external driving laser to the atoms, which is red detuned from the cavity mode by one vibrational quantum, induces cavity-enhanced sideband cooling. For a dense and cold enough atomic ensemble we predict an oscillation threshold for optical Raman sideband lasing concurrent with coherent matter-wave amplification. Above this oscillation threshold photons and atoms in the lowest band are dominantly created pairwise via stimulated emission with a strong suppression of competing spontaneous processes. In close analogy to a nondegenerate parametric oscillator we find sub-Poissonian photon statistics and almost perfect nonclassical atom-photon number correlations. Injecting atoms in higher vibrational bands via tunneling or incoherent scattering then leads to continuous, simultaneous generation of a coherent atom beam and laser light with nonclassical atom-field correlations.

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Thomas Salzburger, Helmut Ritsch. 2007-12-18. Twin stimulated amplification of light and matter waves in an atom-photon pair laser. https://doi.org/10.1103/physreva.77.063620

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