Entanglement in the above-threshold optical parametric oscillator
Alessandro S. Villar, K. N. Cassemiro, K. Dechoum, Antonio Zelaquett Khoury, M. Martinelli, P. Nussenzveig · Journal of the Optical Society of America B · 2007
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 Δ2p̂−=0.50(1), or −3.01(9) dB, and in the sum of phase quadratures they are Δ2q̂+=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 the discrepancies with theory are discussed.