The detection of carbon monoxide by the second harmonic generation of CO₂ laser

Abstract

Abstract:The technique of Second-Harmonic Generation (SHG) of CO2 laser for carbon monoxide concentration detection is investigated in this paper. A simple mechanical Q-switched CO 2 laser is used in our experiment, which works at 9.586 µm. The nonlinear optical crystal used for frequency doubling is ZnGeP2. Different CO concentration detections are performed and 100ppm detectable sensitivity is obtained.

Model studies of THz-range generation by down-conversion in GaSe and GaSeS crystals

“…Modified properties and improved efficiencies are reported for a number of doped crystals: light (GaSe:S) and heavely S-doped GaSe crystals that also referred to as solid solution crystals GaSe:GaS (GaSe 1-x S x , where x is mixing ratio) 12,13,14,15,16 , GaSe:In and Ga 1-x [36][37][38][39][40] , which consider some other double element doped GaSe crystals. Strengthened structuregives opportunity of the application in out-of-door applied systems 41 .…”

Aspects for efficient wide spectral band THz generation via CO2laser down conversion

“…Fortunately, an original ε-polytype structure of GaSe is strengthening by isovalent element doping as well other physical properties responsible for frequency conversion efficiency are modifying that, respectively, allowed easier cut & polishing at arbitrary directions and improves in the frequency conversion efficiency. Strengthened structure gives opportunity of the application in out-of-door applied systems 10 . Modified properties and improved efficiencies are reported for a number of doped crystals: light (GaSe:S) and heavely S-doped GaSe crystals or so called solid solution crystals GaSe 1-x S x (GaSe:GaS) 11,12,13,14,15 , GaSe:In and Ga 1-x In x Se 16,17,18,19,20 , GaSe:Te and GaSe 1-x Te x 18,21,22 , doped GaSe:Er 23,24 and GaSe:Al 25 crystals.…”

High power 4.65 μm single-wavelength laser by second-harmonic generation of pulsed TEA CO2 laser in AgGaSe2 and ZnGeP2

“…Both bands are of great interest for many applications especially in the long distance situation because they are in the atmospheric trans mission window, such as environmental measure ments, laser radar and so on [1][2][3][4][5][6][7][8][9][10][11][12][13]. For a continuous wave (CW) operation, the optical conversion effi ciency for SHG of CO 2 laser is in the range of 10 -4 -10 -3 , which is too low to use practically [14,15].…”