Research Article

Mid-infrared Spectrally Pure Single-Photon States Generation from 22 Nonlinear Optical Crystals

Figure 1

The phase-matching function and group-velocity matching functions () for different signal/idler wavelength and phase-matching angle (polar angle) for AGSe crystal (a) and phase-matching (azimuth angle) angle for LISe crystal in the xy plane (b). In this calculation, we consider the type-II phase-matching condition with collinear and wavelength-degenerate (2 =  = ) configuration.
(a)
(b)