Physical origins of double peak phase matching in GaSe

Double peak phase matching was recorded during experimental study of parametric frequency converters based on GaSe, its solid solutions crystals like GaSe1-xSx and ZnGeP2. Its physical origins are identified as presence of twin, large difference between cut and PM angles, self-heating effect at appropriate conditions, mismatched second (Φ) phase matching angle and microdefects. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only