Entanglement in the above-threshold optical parametric oscillator

Alessandro S. Villar, Katiúscia N. Cassemiro, Kaled Dechoum, Antonio Z. Khoury, Marcelo Martinelli, Paulo Nussenzveig
2007 Journal of the Optical Society of America. B, Optical physics  
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
more » ... p power is presented, and discrepancies with theory are discussed.
doi:10.1364/josab.24.000249 fatcat:kvtev3xbuvguhm4bl3u7sjryiu