Quadrature entanglement and photon-number correlations accompanied by phase-locking
Hayk H. Adamyan, N. H. Adamyan, Suren B. Manvelyan, Gagik Yu. Kryuchkyan · Physical Review A · 2006
We investigate quantum properties of phase-locked light beams generated in a nondegenerate optical parametric oscillator (NOPO) with an intracavity waveplate. This investigation continues our previous analysis presented in Phys. Rev. A 69, 053814 (2004), and involves problems of continuous-variable quadrature entanglement in the spectral domain, photon-number correlations as well as the signatures of phase-locking in the Wigner function. We study the role of phase-localizing processes on the quantum correlation effects. The peculiarities of phase-locked NOPO in the self-pulsing instability operational regime are also cleared up. The results are obtained in the $P$-representation as a quantum-mechanical calculation in the framework of stochastic equations of motion, as well as by numerical simulation based on the method of quantum state diffusion.