Output power and spectrum of optical parametric generator in the superfluorescent regime.

Explicit expressions for the irradiance and signal spectrum of an optical parametric generator were derived. The calculation is in quantitative agreement with measurements of parametric generators with three different lengths of crystals operating in the superfluorescent regime. The measured spectrum was predicted for the entire measured range up to a gain-length product of 16, and the measured signal power was accurately derived up to a gain-length product of 10.

Polarization-mixing optical parametric oscillator.

We report the experimental realization of a new type of optical parametric oscillator in which oscillation is achieved by polarization rotation in a linear retarder, followed by nonlinear polarization mixing. The mixing is performed by a type II degenerate parametric downconversion in a periodically poled KTP crystal pumped by a 1064 nm pulsed Nd:YAG pump. A single, linearly polarized beam, precisely at the degenerate wavelength is generated. The output spectrum has a narrow linewidth (below the instrumentation bandwidth of 1 nm) and is highly stable with respect to variations in the crystal temperature.

Temperature-dependent Sellmeier equation for the refractive index of stoichiometric lithium tantalate.

We present a temperature-dependent Sellmeier equation for the refractive index of stoichiometric LiTaO3. The extraordinary refractive index, for the range 0.39-4.1 microm and for temperatures of 30-200 degrees C, are based on previously published data [Jpn. J. Appl. Phys. 41, 465 (2002)] and on measured data derived from quasi-phase-matched (QPM) resonances. We used the new Sellmeier coefficients that we obtained to calculate the QPM wavelengths for an optical parametric oscillator (OPO) based on periodically poled stoichiometric LiTaO3 pumped at 1064 nm. The measured wavelengths of the OPO were in good agreement with our predictions.