Efficient continuous-wave frequency doubling of a tunable CO_2 laser in AgGaSe_2

Abstract

Second-harmonic output at 4.6-5.5 mum of the order of 6 mW with a 0.12% external conversion efficiency has been obtained by pumping a AgGaSe(2) crystal with a low-power cw CO(2) laser. The surface damage threshold of AgGaSe(2) for cw radiation was found to be inside the limit of 33-45 kW/cm(2) in the 9.2-10.8-mum wavelength region. Another important limitation of the pump power connected with a thermal lensing effect in crystal was determined experimentally. A comparison was made of AgGaSe(2) and ZnGeP(2) crystals as materials suitable for the efficient generation of the second harmonic of cw CO(2) laser radiation.

Synthesis and growth of nonlinear infrared crystal material AgGeGaS4 via a new reaction route

“…The transmittance absorption coefficient was calculated (Fig. 3b) utilizing the equation [11]: where L is the length of the sample, T is the transmission, and R=(nÀ1) 2 /(n+1) 2 is the Fresnel power reflection coefficient. The figure (Fig.…”

Conceptual Design of a Dispersion Interferometer Using a Ratio of Modulation Amplitudes

“…A threshold P l for the thermal-lensing effect of 2 kW/cm 2 is reported in Ref. 13 and is smaller than P sd . Thus, allowable beam waist is determined by P l .…”

“…Table 1 [13][14][15] summarizes its properties. The conversion efficiency η = P 2ω /P ω , where P 2ω and P ω are the powers of the second harmonic and the fundamental, respectively, is given by [15] …”

Growth of large size AgGaGeS4 crystal for infrared conversion

“…The optical absorption coefficient was calculated utilizing the following equation [9] based on the above measured data of the transmission spectra.…”