Quantum theory analysis of twin-photon beams generated by parametric fluorescence

Integrated nonlinear optic devices for generation of twin photon beams are expected to be a key device for the development of quantum information techniques. This paper presents a systematic quantum theory analysis on generation of twin photons by parametric fluorescence and properties of the twin photon beams. The analysis uses multimode-pair description including phase mismatched cases. Full description of the quantum states of the twin photon beams is obtained. Mathematical expressions for photon numbers, photon beam powers, efficiency, wavelength bandwidth, and photon correlation are deduced. Numerical data are given for several types degenerate and nondegenerate quasi-phase matched LiNbO/sub 3/ waveguide twin-photon generation devices.