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Frequency down conversion through Bose condensation of light

Patrick Navez
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Abstract

We propose an experimental set up allowing to convert an input light of wavelengths about $1-2 μm$ into an output light of a lower frequency. The basic principle of operating relies on the nonlinear optical properties exhibited by a microcavity filled with glass. The light inside this material behaves like a 2D interacting Bose gas susceptible to thermalise and create a quasi-condensate. Extension of this setup to a photonic bandgap material (fiber grating) allows the light to behave like a 3D Bose gas leading, after thermalisation, to the formation of a Bose condensate. Theoretical estimations show that a conversion of $1 μm$ into $1.5 μm$ is achieved with an input pulse of about $1 ns$ with a peak power of $10^3 W$, using a fiber grating containing an integrated cavity of size about $500 μm \times 100 μm^2$.

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Patrick Navez. 2002-09-11. Frequency down conversion through Bose condensation of light. https://doi.org/10.1103/physreva.68.013811

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