Eiko Takaoka

Sellmeier and thermo-optic dispersion formulas for KTP

KTP has been found to be phase matchable for type-2 second-harmonic generation of the third harmonics of the CO2 laser wavelengths at 9.2714 and 9.5525 microm at 20.0 degrees C. The resulting angle and temperature-tuning data combined with the literature values of the Nd:YAG laser-pumped optical parametric oscillator were used to improve the Sellmeier equations and the thermo-optic dispersion formula that reproduce well the temperature-tuned 90 degree phase-matching conditions of the flux-grown crystals. Applications to quasi phase matching are presented.

90 degrees phase-matched third-harmonic generation of CO(2) laser frequencies in AgGa(1-x)In(x)Se(2).

AgGa(1-x) In(x)Se(2) with x=0.474 was found to be 90 degrees phase matchable for third-harmonic generation of CO(2) laser wavelengths 9.2714-10.5910 mum by means of temperature tuning. Sellmeier equations and the thermo-optic constant for this crystal are presented.

200-mW-average power ultraviolet generation at 0.193 μm in K 2 Al 2 B 2 O 7

K2Al2B2O7 has been found to be phase matchable for type-1 sum-frequency generation (SFG) at 0.193 microm by mixing the Nd:YAG laser wavelength at 1.0642 microm and the SFG output of the RbTiOAsO4 optical parametric oscillator tuned at 0.2358 microm. An average power of 200 mW at 10 kHz was obtained in a 7-mm-long crystal. In addition, the Sellmeier equations and the thermo-optic dispersion formula, which predict well the phase-matching conditions and temperature phase-matching bandwidths (FWHM) for second-harmonic generation and SFG in the 0.193-0.669-microm range, are presented.

Thermo-optic dispersion formula for AgGaS 2

AgGaS(2) has been found to be 90 degrees phase matchable at 192 degrees C for sum-frequency mixing between the output of the KTP parametric oscillator at 3.2627 microm and its pump source at 1.0642 microm. The thermo-optic dispersion formula that can be used for good reproduction of the temperature-dependent phase-matching conditions thus far reported in the literature as well as our new data for second-harmonic generation of a CO(2) laser and its harmonics at 1.7652-5.2955 microm is presented.

Temperature Phase-Matching Properties for Harmonic Generation in GaSe

The high accuracy Sellmeier equations of GaSe were constructed from the phase-matching conditions for harmonic generation of a CO2 laser and published refractive indices. The high accuracy thermo-optic dispersion formula is also presented.

Temperature-Insensitive Second-Harmonic Generation at 0.5321 µm in YCa4O(BO3)3

YCa4O(BO3)3 has been found to have the phase-matching points where the temperature variation of the phase-matching angle (dθobs/dT) becomes zero for type-1 second-harmonic generation at 0.5321 µm at θ=30.8° and =180°. We also found that the temperature sensitivity of the phase-matching angle in the zx plane differs between the =0° and =180° propagation directions in this material. In addition, the thermo-optic dispersion formula of YCa4O(BO3)3 is presented.

Thermo-optic dispersion formula for RbTiOAsO4

The thermo-optic constants of the flux grown RbTiOAsO4 (RTA) have been measured from 0.4577 to 0.7931 µm. These results were fitted to the temperature phase-matching bandwidths (FWHM) for harmonic generation of the Nd:YAG laser and the Nd:YAG laser-pumped KTiOAsO4 (KTA) optical parametric oscillator (OPO), and were used to construct the thermo-optic dispersion formula that can be used for good reproduction of the temperature-dependent phase-matching conditions in the 0.459–3.129 µm range. Applications to the quasi phase-matching are presented.

New data on the phase-matching properties of YCa 4 O(BO 3 ) 3

YCa4O(BO3)3 has been found to be 90° phase-matchable for type-1 SHG at 0.8325 µ m along z. In addition, we report the new experimental data on the phase-matching properties of YCa4O(BO3)3 together with the improved Sellmeiers equations that reproduce well our new experimental results.

High-efficiency, 90/spl deg/ phase-matched SHG at 5.2955 /spl mu/m in AgGa/sub 1-x/In/sub x/Se/sub 2/

Summary form only given. A salient feature of AgGa/sub 1-x/In/sub x/Se/sub 2/ is 90/spl deg/ phase-matched second and third harmonic generation (SHG and THG) of CO/sub 2/ laser frequencies. Also there is crystal parametric oscillation in the mid IR on pumping. Here, we report on the high-efficiency (45%), high average power (8 W) SHG of a CO/sub 2/ laser at frequencies of 10.5910 /spl mu/m in this mixed crystal.

Temperature-tuned, 90/spl deg/ phase-matched parametric oscillator using AgGa/sub 1-x/ In/sub x/Se/sub 2/

Summary form only given. This paper reports the high-efficiency operation of tunable 3-5-/spl mu/m source for infrared counter-measures. A periodically poled RTiO-AsO/sub 4/ parametric oscillator (OPO) pumped by a LD pumped Nd:YAG laser was used to drive AgGa/sub 1-x/In/sub x/Se/sub 2/ (AGISE) parametric oscillator. An average output power of 1.5 W with an overall energy conversion efficiency of 30% was obtained at 5 kHz under 90/spl deg/ phase-matching conditions. The wavelength coverage was 3.65-5.10 /spl mu/m.