High-energy Optical Parametric Oscillator Research Articles

Investigations on beam quality improvement of an NCPM-KTA-based high energy optical parametric oscillator using an unstable resonator with a Gaussian reflectivity mirror [Invited

Investigations on beam quality improvement of an NCPM-KTA-based high energy optical parametric oscillator using an unstable resonator with a Gaussian reflectivity mirror [Invited

Numerical study of high-energy optical parametric oscillator with top-hat pump intensity profile and quasi-phase-matched crystal with wedge-shaped domain

We present a numerical study for the design of efficient MgO :PPLN based pulsed nanosecond optical parametric oscillator (OPO), with input pump pulses of top-hat transverse intensity profile, and a double-pass pump cavity configuration. In particular, we investigate the effect of domain shape on the conversion efficiency. We considered two types of domain structures: "perfect vertical-wall" and "wedge-shaped" domains and our numerical results show that at higher pump pulse energies, the conversion efficiency saturates, and the saturated efficiency is almost independent of the domain shapes. Based on our study, we also propose a new scheme for development of compact high-power OPO sources using MgO :PPLN chips of relatively short lengths and large cross-sectional area.

Compact, high-pulse-energy, picosecond optical parametric oscillator

We report a high-energy optical parametric oscillator (OPO) synchronously pumped by a 7.19 MHz, Yb:fiber-amplified, picosecond, gain-switched laser diode. The 42-m-long ring cavity maintains a compact design through the use of an intracavity optical fiber. The periodically poled MgO-doped LiNbO(3) OPO provides output pulse energies as high as 0.49 μJ at 1.5 μm (signal) and 0.19 μJ at 3.6 μm (idler). Tunability from 1.5 to 1.7 μm and from 2.9 to 3.6 μm is demonstrated, and typical M(2) values of 1.5 × 1.3 and 2.8 × 1.9 are measured for the signal and idler, respectively, at high power.

Improved beam quality from a high energy optical parametric oscillator using crystals with orthogonal critical planes

We demonstrate with simulations and experiments that an optical parametric oscillator using two different crystals with orthogonal walk-off planes can generate a symmetric, high-quality beam even if the resonator has a high Fresnel number. In the experiments we used KTA and BBO crystals to convert 5 ns pulses at 1.06 microm to 1.7 microm pulses with more than 10 mJ energy and beam quality M(2) approximately 2.

Frequency-tunable optically pumped carbon monoxide laser

Single-line frequency-tunable lasing was observed in an optically pumped, repetitively pulsed, room-temperature CO laser for the first time. The R(0) and R(7) ro-vibrational transitions in the (2,0) overtone of CO at 2.3 /spl mu/m were optically pumped with a high-energy optical parametric oscillator. Single-line lasing was observed on (2,1) P(2)-P(17) transitions and R(0)-R(11) transitions (covering wavelengths within the range 4.6-4.9 /spl mu/m) when using a diffraction grating as the spectrally selective reflector of the laser resonator. The observed CO laser pulse lengths were /spl sim/10/sup -7/ s with peak power up to 10/sup 4/ W. The influence of CO pressure, the addition of buffer gas (He, Ar), Q-factor of the laser resonator, and the pump pulse energy on CO laser pulse temporal characteristics and output energy spectral distribution was studied experimentally.