High-efficiency mid-infrared optical parametric oscillator based on PPMgO:CLN

Abstract

The experimental results of a high-efficiency mid-IR laser are presented on a quasi-phase-matched single-resonated optical parametric oscillator in PPMgO:CLN pumped by a 1064 nm laser of an elliptical beam. The pump source was an acousto-optical Q-switched cw-diode-side-pumped Nd:YAG laser. The beam polarization matched the e-ee interaction in PPMgO:CLN. When the crystal was operated at 110 degrees C and the pump power was 104 W with a repetition rate of 7 kHz, average output powers of 16.7 W at 3.84 microm and 46 W at 1.47 microm were obtained. The slope efficiency of the 3.84 microm laser with respect to the pump laser was 19.1%. The M(2) factors of the 3.84 mum laser were 2.03 and 5.89 in the parallel and perpendicular directions, respectively.

Output characteristics of a singly-resonant optical parametric oscillator: Dependence on the variation of the signal and idler output coupling

“…In addition to this result, if we consider the fact that the slope efficiency is always larger than the corresponding conversion efficiency for any SRO, we speculate one can obtain the output power of idler more than 5.6 W with the reflectivity at the idler wavelength lower than 80% if G is larger than 1.3. This speculation is supported by the previous work in which Peng et al 14 Table 2, it can be also found that the power ratio ξ exp varies from 0.98 to 1.35. In general, for a generation of signal and idler in each single-pass, amplified intensity ratio of signal to idler must be the same as ξ because the generated number of signal photons is the same as that of idler photons.…”

“…Thus, a double-pass pump SRO with a plane-parallel two-mirror cavity can be one of the best choices of cavity configuration because of its compactness and easy alignment. In this way, a power conversion efficiency as high as 10-20% for generation of infrared radiation was achieved with an average power of more than 5 W. 6,[10][11][12][13][14][15][16][17][18] For output radiation in the 2.2-4 µm region (corresponding to idler when SRO is pumped by 1.064 µm-Nd : YAGlaser), in most researches infrared radiation at the idler wavelength was obtained by using SRO S with an output coupler of high reflectivity at the signal wave. 6,10,12,[15][16][17][18] On the other hand, Peng et al also obtained infrared radiation of wavelength 3.84 µm with a high conversion efficiency of 16% by using SRO I.…”

Tm:YLF laser-pumped periodically poled MgO-doped congruent LiNbO_3 crystal optical parametric oscillators

“…Quasi-phase matching OPO combines the advantages of collinear propagation of the pump and the generated waves with no walk-off in space, large acceptance angle, and possibility of using the largest nonlinear optical tensor element. Through this method, substantial studies have been implemented to achieve laser in the mid-IR region based on a singly resonant OPO (SRO) constructed with periodically poled lithium niobate (PPLN) pumped by 1 μm lasers [4,5]. However, the conversion efficiency was confined, not exceeding the quantum limit set by the Manley-Rowe relations.…”

High repetition frequency PPMgOLN mid-infrared optical parametric oscillator

“…However, the damage threshold of PPMgOLN is as low as 10 J/cm 2 (1064 nm, 10 ns pulse) [4], so raising the repetition frequency of the pulse is an effective way to improve the power of the lights generated by OPO. By now, the frequency of the mid-infrared (3 -5 μm) laser produced by PPMgOLN is 1 -50 kHz [5][6][7], and the efficiency from the pump to the mid-infrared laser could reach as high as about 20%.B. Wu et al [5] recently reported the 52 kHz OPO with the mid-infrared wavelength of 3.82 μm, the power of 9.23 W, and the efficiency of 19.3%.…”

“…In 2009, Y.F. Peng et al [6] realized the 16.7 W mid-infrared laser with the wavelength of 3.82 μm at the repetition frequency of 7 kHz. In 2007, X. Liang et al [7] reported the 10 kHz OPO, and the efficiency from the pump to the signal and the idler was 34% with the method of non-colinear phasematch.…”