Double-pump-pass singly resonant optical parametric oscillator for efficient generation of infrared light at 2300 nm based on PPMgSLT

The pump laser was a cw-diode-pumped, acousto-optically Q-switched Nd:YAG laser. The laser had a pulse width of ~85 ns when operating at 10 kHz repetition rates. For infrared output of 2300 nm, we used 35-mm-long PPMgSLT which has a grating period of 32.7 μm for the first-order quasi-phase matching, resulting in the signal wavelength of 1980 nm at the crystal temperature of 76.5oC. Our optical parametric oscillator (OPO) was of a simple linear extra-cavity structure, formed by two flat dichroic mirrors with a separation of ~45 mm. The input coupling mirror had a high transmission of 98% for the pump, high reflectance of 98% at the signal and idler wavelengths, whereas the output coupler had a high reflectance of 98% at the pump wavelength. Hence, the OPO can be considered as singly resonant with double-pass pumping. In order to find an optimum reflectance for the efficient generation of infrared radiation of 2300 nm, we used the three different output mirrors whose reflectivity are ranging from 90% to 38% at the signal wavelength. We measured the signal and idler power as a function of the pumping power of Nd:YAG laser for three different output couplers. A maximum extraction efficiency with an optimum reflectance of output mirror was 27% for the idler, corresponding to 5.6 W of average output power. The fluctuations in the idler root-mean-square output power were measured to be below 1.5%. Our result is comparable with the recent one based on PPLN even with a simple cavity.

[1]  I. Shoji,et al.  Temperature-Dependent Sellmeier Equation for Refractive Index of 1.0 mol % Mg-Doped Stoichiometric Lithium Tantalate , 2013 .

[2]  B. Foy,et al.  The holmium:yttrium-aluminum-garnet laser in wrist arthroscopy: a five-year experience in the treatment of central triangular fibrocartilage complex tears by partial excision. , 2001, The Journal of hand surgery.

[3]  P. Schunemann,et al.  Grating tunable 4-14 µm GaAs optical parametric oscillator pumped at 3 µm. , 2014, Optics express.

[4]  P. Schunemann,et al.  Broadly tunable noncritically phase-matched ZnGeP2 optical parametric oscillator with a 2-microJ pump threshold. , 2003, Optics letters.

[5]  Konstantin L. Vodopyanov,et al.  ZnGeP 2 optical parametric oscillator with 3.8–12.4-µm tunability , 2000 .

[6]  Valentin Petrov,et al.  Noncritical singly resonant optical parametric oscillator operation near 6.2 microm based on a CdSiP(2) crystal pumped at 1064 nm. , 2009, Optics letters.

[7]  J. Lam,et al.  Treatment of proximal ureteral calculi: holmium:YAG laser ureterolithotripsy versus extracorporeal shock wave lithotripsy. , 2002, The Journal of urology.

[8]  M. Eichhorn,et al.  Tunable Mid-infrared ZnGeP2 RISTRA OPO pumped by periodically-poled Rb:KTP optical parametric master-oscillator power amplifier. , 2012, Optics express.

[9]  Ki-Ho Cho,et al.  Studies of the output efficiency of signal wave as a function of reflectance of output coupler in nanosecond single-resonant optical parametric oscillators , 2009, LASE.

[10]  Xingbin Wei,et al.  High-efficiency mid-infrared optical parametric oscillator based on PPMgO:CLN. , 2009, Optics letters.

[11]  Aleksey Tyazhev,et al.  Subnanosecond, 1 kHz, temperature-tuned, noncritical mid-infrared optical parametric oscillator based on CdSiP(2) crystal pumped at 1064 nm. , 2010, Optics letters.

[12]  J. L’huillier,et al.  Non-collinear nanosecond optical parametric oscillator based on periodically poled LN with tilted domain walls , 2007 .

[13]  L. Becouarn,et al.  Optical parametric oscillation in quasi-phase-matched GaAs , 2004, Conference on Lasers and Electro-Optics, 2004. (CLEO)..

[14]  T. Taira,et al.  High-energy quasi-phase-matched optical parametric oscillation in a periodically poled MgO:LiNbO3 device with a 5 mm x 5 mm aperture. , 2005, Optics letters.

[15]  Toomas H. Allik,et al.  Advances in optical parametric oscillators with application to remote chemical sensing , 1998, Defense, Security, and Sensing.

[16]  M. Fejer,et al.  Quasi-phase-matched optical parametric oscillators in bulk periodically poled LiNbO 3 , 1995 .

[17]  M. Fejer,et al.  Multigrating quasi-phase-matched optical parametric oscillator in periodically poled LiNbO(3). , 1996, Optics letters.

[18]  Qiang Liu,et al.  High repetition frequency PPMgOLN mid-infrared optical parametric oscillator , 2010 .