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Tunable CW optical parametric oscillator optimum operating conditions, using barium, sodium and lithium niobate crystals parametric fluorescence tuning curves for comparison
Threshold of parametric oscillator system with idler modes in same frequency spacing as laser pump source
Tunable optical parametric oscillator using argon laser CW output as pump and lithium niobate as nonlinear crystal
Tunable optical parametric oscillators including Gaussian beams amplification, threshold, tuning techniques, spectral output, etc
We show that a nondegenerate multi-frequency parametric oscillator has different properties compared with an usual three-wave parametric oscillator. We consider, as an example, a scheme of a resonant cw monolithic microwave-optical parametric oscillator based on high-Q whispering gallery modes excited in a nonlinear dielectric cavity. In this paper we recall main properties of usual three-mode OPO, discuss four-mode OPO, study conditions of generation of a frequency comb in all-resonant OPO with two-frequency optical pumping, and discuss stability of a cavity with moving mirrors.
Singly resonant optical parametric oscillator allowable pump bandwidth
An AgGaSe2 optical parametric oscillator, pumped by a 1.73-micron Er:YLF laser, has demonstrated reproducible low thresholds, 3.6 mJ, and high-slope efficiencies, 0.31. Threshold and slope efficiency were investigated as a function of resonator length. Spectral bandwidth was measured and correlated with the beam divergence of the pump laser.
Tuning of both the pump laser, a Ho:Tm:YLF laser operating on the 5 I 7 - 5 I 8 transition, and an AgGaSe2 parametric oscillator has been demonstrated. Tuning of the Ho:Tm:YLF laser is complicated but not frustrated by the existence of both CO2 and H2O lines in the vicinity of the laser transition. Tuning of the parametric oscillator was achieved by tuning of the pump laser. Injection seeding of the parametric oscillator on the nonresonant signal was also demonstrated. In addition, the measured efficiencies of the parametric oscillator were compared by two different methods, measuring the parametric-oscillator output energy and measuring the energy depleted from the pump. By comparison of these measurements, the intrinsic efficiency of the parametric oscillator cab be determined
It is pointed out that tunable coherent sources are very useful for many applications, including spectroscopy, chemistry, combustion diagnostics, and remote sensing. Compared with other tunable sources, optical parametric oscillators (OPO) offer the potential advantage of a wide wavelength operating range, which extends from 0.2 micron to 25 microns. The current status of OPO is examined, taking into account mainly advances made during the last decade. Attention is given to early LiNbO3 parametric oscillators, problems which have prevented wide use of parametric oscillators, the demonstration of OPO's using urea and AgGaS2, progress related to picosecond OPO's, a breakthrough in nanosecond parametric oscillators, the first demonstration of a waveguide and fiber parametric amplification and generation, the importance of chalcopyrite crystals, and theoretical work performed with the aim to understand the factors affecting the parametric oscillator performance.
Tunable optical continuous wave parametric oscillator using 5145 angstrom Ar laser pump and lithium niobate as nonlinear material, noting large oscillation bandwidth
Noncollinear single cavity optical parametric oscillation with specified energy conversion using ruby laser-pumped lithium niobate, discussing tuning
CW visible ring cavity parametric oscillator, discussing pump depletion, conversion efficiency and improved stability resulting from optical isolation
A doubly resonant optical parametric oscillator (DRO) pumped with the second harmonic of a narrow-linewidth Nd:YAG laser is described. The linewidth of the DRO signal was less than 13 kHz, the DRO was shown to generate a phase-locked subharmonic of the pump at degeneracy, and the signal and the idler were shown to be mutually coherent with the pump and to be phase-anticorrelated with each other away from degeneracy. The signal-idler heterodyne linewidth was 500 Hz, and pump phase modulation was shown to transfer to the DRO phase at degeneracy.
Average power effects relative to the operation of parametric oscillators and amplifiers have been calculated. Temperature gradients have been calculated for both radial and longitudinal heat extraction. In many instances, the thermal load on a parametric oscillator is higher than the thermal load on a parametric amplifier with the same pump power. Having one or both these wavelengths resonant increases the chances that a generated photon will be absorbed by the nonlinear crystal. Temperature profiles and thermal diffusion time constants have been calculated for Gaussian beams, given the heat-deposition rate. With radical heat extraction the temperature profile can be expressed in a power series or approximated by a Gaussian distribution function.
Optical parametric oscillator output /signal/ frequency locked to absorbing atomic transition, discussing effective linewidth
Solid-state lasers are developed for atmospheric applications. Optical parametric oscillators (OPO) are being investigated as sources of tunable radiation in the 2.5-12 micron range where development of conventional lasers is subject to numerous difficulties. Parametric oscillation is a nonlinear optical technique for converting laser output to longer wavelengths. Incident photons, typically from a pulsed pump laser, are converted into two photons of longer wavelength, while satisfying energy conservation. The particular split of energy is determined by momentum conservation; the wavelength of interest is usually selected by angle orientation of the nonlinear material with respect to the direction of propagation of the pump beam. An OPO based on AgGaSe2 was considered.
This viewgraph presentation summarizes the hyper-parametric oscillations observations of the fluorite resonator. The reporters have observed various nonlinear effects in ultra-high Q crystalline whispering gallery mode (WGM) resonators. In particular, it was demonstrated a low threshold optical hyper-parametric oscillations in a high-Q (Q=1010) CaF2 WGM resonator. The oscillations result from the resonantly enhanced four-wave-mixing occurring due to Kerr nonlinearity of the material.
Pumping laser bandwidth requirement for optical parametric oscillators