Efficient RTP-based OPO intracavity pumped by an acousto-optic Q-switched Nd:YVO_4 laser

Abstract

This Letter describes an intracavity pumped optical parametric oscillator (OPO) based on noncritical phase matching RbTiOPO4 (RTP) crystal driven by a laser diode end-pumping acousto-optic Q-switched Nd:YVO4 laser. Simultaneous efficient signal light at 1.6 μm and idler light at 3.1 μm outputs were obtained. At an incident pump power of 10.5 W and a Q-switching pulse repetition frequency of 60 kHz, 1.42 W at center wavelength of about 1619 nm and 0.38 W at 3108 nm were achieved, with the diode to OPO total output conversion efficiency up to 17.1%. The pulse width is about 6.5 ns for the signal light corresponding to the fundamental light at 1064 nm of about 10 ns. The spectral widths of the signal and idler light are narrower than 0.5 and 1.0 nm. The result shows that the RTP crystal is an efficient crystal to generate eye-safe and mid-infrared lights by making full use of noncritical phase matching.

A Wavelength-Agile Eye-Safe Optical Parametric Oscillator Based on an X-Cut KTP Crystal

“…The eyesafe OPO has been a research hotspot in the field of solid-state lasers in the past two decades. A group of mature bulk nonlinear crystals must be mentioned, that is, the KTP family [13][14][15] (including KTP, KTA, RTP, etc. ), as they are the most popular OPO materials to generate eye-safe lasers in the noncritical phase matching (NCPM) scheme by fully using their high damage threshold, large nonlinear coefficient, large acceptance angle, no walk off and being applicable for multimode pumping.…”

Mid-Infrared Tunable Intracavity Singly Resonant Optical Parametric Oscillator Based on MgO:PPLN

“…Recently, there are a number of reports on CW extracavity OPO (EOPO) pumped by well-refined solid-state lasers and fiber lasers [12][13][14][15]. Compared with this extracavity OPO, intracavity OPO (IOPO) is characteristic of high energy density in nonlinear medium, compact structure, and multiple round trips of pump light to increase the effective interaction length [16][17][18][19][20]. Hence, the output power and optical-optical conversion efficiency of IOPO are higher than EOPO.…”

Diode-Pumped Nd:YAP Intracavity Optical Parametric Oscillator Emitting at 1603 nm: Influence of Energy-Transfer Upconversion

“…4 I 11=2 transition band only reached 1573 nm [10]. Although it is a relatively new RTP nonlinear material, as well as an isomorph of the KTP crystal, was recently developed to produce the signal emission longer than 1.6 m [15], [16], at least one shared optical components usually make their laser output rather sensitive when one attempts to individually align the fundamental and OPO cavities for optimizing the conversion efficiency with high stability.…”