High-pulse-energy high-efficiency mid-infrared generation based on KTA optical parametric oscillator

• Published in: Applied physics. B, Lasers and optics Lasers and optics, 2010-09, Vol.100 (4), p.749-753
• Main Authors: Zhong, K., Yao, J. Q., Xu, D. G., Wang, J. L., Li, J. S., Wang, P.
• Format: Article
• Language: English
• Subjects: Conversion; Crystals; Diodes; Direct power generation; Doped-insulator lasers and other solid state lasers; Engineering; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Holes; Lasers; Nonlinear optical crystals; Nonlinear optics; Optical Devices; Optical materials; Optical parametric oscillators and amplifiers; Optics; Photonics; Photons; Physical Chemistry; Physics; Physics and Astronomy; Quantum Optics; Wavelengths
• ISSN: 0946-2171; 1432-0649
• DOI: 10.1007/s00340-010-3932-y

A high-energy, high-efficiency mid-infrared KTA OPO at 3.47 μm intracavity pumped by a Nd:YAG laser is presented. The maximum output energy is 31 mJ at the repetition rate of 10 Hz with a V-shaped cavity, corresponding to the absolute optical-to-optical conversion efficiency of 4.76% from the diode and the photon conversion efficiency of 87% from the fundamental to mid-infrared energy. The pulse width is 5.8 ns at the maximum output energy and the peak power reaches higher than 5 MW. The line width of the mid-infrared wave is about 1.1 nm (or 0.9 cm −1 in wave number). The output energy demonstrates good stability. To our knowledge, these are the highest pulse energy and conversion efficiency of mid-infrared OPOs using bulk nonlinear crystals in the 3–5 μm range.