A high energy 3.75 mu m KTA optical parametric oscillator at a critical angle

作者：Liu, Qiang^*; Liu, Jianhui; Zhang, Zilong; Gong, Mali

来源：Laser Physics Letters, 2013, 10(7): 075407.

DOI：10.1088/1612-2011/10/7/075407

• POLED MGO-LINBO3 DEVICE
• CRYSTAL
• RANGE

A high energy 3.75 mu m nano-second KTiOAsO4 (KTA) optical parametric oscillator (OPO) at a critical angle is demonstrated in this letter. The OPO is pumped by a 1.064 mu m laser and the KTA crystal is cut at 41.2 degrees in the XZ plane. The phase matching angle is at the edge of the phase match curve and the edge of the absorption region for mid-infrared lasers. The cavity is a signal resonant oscillator. The spatial distribution of the pump light is a quasi-plane wave and the pulse width is 10 ns. A 218 mJ signal at 1.484 mu m and a 60 mJ idler at 3.75 mu m are achieved with a pump energy of 795 mJ, corresponding to a conversion efficiency of 35%. The idler pulse width is 7 ns. The divergence angle in the walk-off plane is 4 mrad and it is 14 mrad in the other plane. The results prove that the OPO phase matching of KTA exists at 3.75 mu m and the KTA OPO can generate a high energy idler at 3.75 mu m.

• 出版日期2013-7
• 单位清华大学