Influences of YVO4 optical axis direction deviation on performances of a-cut Nd:YLF/Cr:YAG/ c-cut YVO4 multi-Raman mode laser

LD end-pumped passively Q -switched a -cut Nd:YLF/Cr:YAG/ c -cut YVO 4 Raman laser is investigated for the first time, and SRS processes of 895 cm −1 ( A 1g ), 821 cm −1 ( B 1g ) and 264 cm −1 ( B 2g ) modes are realized. Raman laser output power, temporal, spectral and polarization features are studied, and unusual phenomena of Raman laser output are observed for the first time. The maximum efficient Raman conversions of 895 cm −1 ( A 1g ), 821 cm −1 ( B 1g ) and 264 cm −1 ( B 2g ) modes are achieved with the linearly polarized direction of E p to be about 45 degrees to a or b axis of c -cut YVO 4 crystal. The optical axis orientation of c -cut YVO 4 crystal significantly affect Raman laser spectra and polarization features. With experiments and analysis in-depth, these anomalies are attributed to optical axis direction deviation of c -cut YVO 4 crystal. These findings can help design c -cut YVO 4 multi-Raman mode lasers of high-performance, which have potential applications.