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Stable nondegenerate optical parametric oscillation at degenerate frequencies in Na:KTP

Sheng Feng·Olivier Pfister
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Abstract

We report the realization of a light source specifically designed for the generation of bright continuous-variable entangled beams and for Heisenberg-limited inteferometry. The source is a nondegenerate, single-mode, continuous-wave optical parametric oscillator in Na:KTP, operated at frequency degeneracy and just above threshold, which is also of interest for the study of critical fluctuations at the transition point. The residual frequency-difference jitter is $\pm$ 150 kHz for a 3 MHz cold cavity half-width at half maximum. We observe 4 dB of photon-number-difference squeezing at 200 kHz. The Na:KTP crystal is noncritically phase-matched for a 532 nm pump and polarization crosstalk is therefore practically nonexistent.

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Sheng Feng, Olivier Pfister. 2003-04-11. Stable nondegenerate optical parametric oscillation at degenerate frequencies in Na:KTP. https://doi.org/10.1088/1464-4266/5/3/310

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