Efficient generation of the second harmonic of a nanosecond CO₂laser radiation pulse

Inorganic Crystals for Nonlinear Optical Frequency Conversion

“…With a larger nonlinear susceptibility, AgGaSe2 has been used to efficiently double the 10.6 flm output of a CO 2 laser (145) and in a broadly tunable 2 flm pumped OPO (146), although the latter application is limited in power scaling by residual absorption at 2 flm and the low thermal conductivity of this crystal (147). ZnGeP2, with a nonlinear susceptibility twice as large as that of AgGaSe2' has been used for SHG (with 80% conversion efficiency) and fo urth harmonic generation of 10.6 flm radiation (148). The high thermal conductivity of ZnGeP2 and improved processing to reduce optical absorption permitted operation of an efficient 2 flm-pumped OPO with pump power as large as 13 W without thermal distortions (149).…”

Development of an efficient coherent optical source at 6.04μm

“…Frequency doubling of ammonia laser in a suitable NLO crystal can thus provide efficient coherent radiation around 6.0 lm. Although, frequency doubling efficiency as high as 57%, 56% and 50% of CO 2 laser emission is reported using the Al 3 AsSe 3 [10], AgGaSe 2 [11], and ZnGeP 2 [12] respectively, but to the best of our knowledge, this is the first report on generation of coherent radiation around 6.0 lm by second harmonic generation (SHG) of ammonia laser radiation in a 15 mm long type-I cut AgGaSe 2 crystal.…”

Tunable THz-radiation in a ZnGeP2 single crystal pumped by dual-wavelength degenerate optical parametric oscillator

“…According to a great variety of nonlinear optical crystals (such as GaSe, GaP, LiNbO3, DAST, GaAs), exactly ZnGeP 2 single crystal has the most optimal characteristics for THz generation [7][8][9][10][11]. This single crystal ZnGeP 2 has an absorption coefficient of ~0.02 cm −1 in the wavelength range of 2-3 microns [12][13][14]. Moreover, this single crystal has the highest radiation transmittance in the wavelength range of 90-1000 microns [11].…”