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Compact Source of EPR Entanglement and Squeezing at Very Low Noise Frequencies

Julien Laurat·Thomas Coudreau·Gaelle Keller·Nicolas Treps·Claude Fabre
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Abstract

We report on the experimental demonstration of strong quadrature EPR entanglement and squeezing at very low noise sideband frequencies produced by a single type-II, self-phase-locked, frequency degenerate optical parametric oscillator below threshold. The generated two-mode squeezed vacuum state is preserved for noise frequencies as low as 50 kHz. Designing simple setups able to generate non-classical states of light in the kHz regime is a key challenge for high sensitivity detection of ultra-weak physical effects such as gravitational wave or small beam displacement.

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Julien Laurat, Thomas Coudreau, Gaelle Keller, Nicolas Treps, Claude Fabre. 2004-04-14. Compact Source of EPR Entanglement and Squeezing at Very Low Noise Frequencies. https://doi.org/10.1103/physreva.70.042315

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