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Entanglement in the above-threshold optical parametric oscillator

Alessandro S. Villar·Katiuscia N. Cassemiro·Kaled Dechoum·Antonio Z. Khoury·Marcelo Martinelli·Paulo Nussenzveig
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Abstract

We investigate entanglement in the above-threshold Optical Parametric Oscillator, both theoretically and experimentally, and discuss its potential applications to quantum information. The fluctuations measured in the subtraction of signal and idler amplitude quadratures are $\Delta^2 \hat p_-=0.50(1)$, or $-3.01(9)$ dB, and in the sum of phase quadratures are $\Delta^2 \hatq_+=0.73(1)$, or $-1.37(6)$ dB. A detailed experimental study of the noise behavior as a function of pump power is presented, and discrepancies with theory are discussed.

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Alessandro S. Villar, Katiuscia N. Cassemiro, Kaled Dechoum, Antonio Z. Khoury, Marcelo Martinelli, Paulo Nussenzveig. 2006-10-24. Entanglement in the above-threshold optical parametric oscillator. https://doi.org/10.1364/josab.24.000249

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