Efficient, high-power, ytterbium-fiber-laser-pumped picosecond optical parametric oscillator

Abstract

We report a high-power picosecond optical parametric oscillator (OPO) synchronously pumped by a Yb fiber laser at 1.064 μm, providing 11.7 W of total average power in the near to mid-IR at 73% extraction efficiency. The OPO, based on a 50 mm MgO:PPLN crystal, is pumped by 20.8 ps pulses at 81.1 MHz and can simultaneously deliver 7.1 W of signal at 1.56 μm and 4.6 W of idler at 3.33 μm for 16 W of pump power. The oscillator has a threshold of 740 mW, with maximum signal power of 7.4 W at 1.47 μm and idler power of 4.9 W at 3.08 μm at slope efficiencies of 51% and 31%, respectively. Wavelength coverage across 1.43-1.63 μm (signal) and 4.16-3.06 μm (idler) is obtained, with a total power of ~11 W and an extraction efficiency of ~68%, with pump depletion of ~78% maintained over most of the tuning range. The signal and idler output have a single-mode spatial profile and a peak-to-peak power stability of ±1.8% and ±2.9% over 1 h at the highest power, respectively. A signal pulse duration of 17.3 ps with a clean single-peak spectrum results in a time-bandwidth product of ~1.72, more than four times below the input pump pulses.

High-power PPMgLN-based optical parametric oscillator pumped by a linearly polarized, semi-fiber-coupled acousto-optic Q-switched fiber master oscillator power amplifier

“…According to these requirements, fiber lasers are supposed to be the best candidates among all the OPO pump sources due to their compactness, robustness, excellent beam quality, and simple thermal management schemes [3]. Therefore, fiber-laser-pumped OPOs have been extensively investigated from continuous wave (CW) to ultrashort pulsed operation schemes [4][5][6][7][8][9][10][11][12][13]. Among all these pump sources, fiber lasers with tens to hundreds of nanoseconds are particularly useful in outdoor applications for both environmental monitoring and missile countermeasures because simple linear cavities are applicable to such pump sources converting the pump power to idler output efficiently during each pulse with peak power higher than the CW OPOs and dimensions smaller than the synchronously pumped OPOs.…”

Ultrafast optical parametric oscillator pumped by a vertical external-cavity surface-emitting laser (VECSEL)

“…During the last decades, synchronously-pumped OPOs have been pumped by different ultrafast laser types, including Ti:sapphire lasers [27], Yb-fiber lasers [28,29], Ndand Yb-based solid-state lasers [30], Tm-lasers [31], and thin-disk lasers [32].…”

High Power Yb Fiber Laser With Picosecond Bursts and the Quasi-Synchronously Pumping for Efficient Midinfrared Laser Generation in Optical Parametric Oscillator

“…In 2010, a periodically poled magnesium oxide doped lithium niobate (PPMgLN)-based OPO pumped by a ps Yb fiber laser was reported with a maximum average power of 7.3 W at 1.54 m and 3.1 W at 3.4 m in pulse duration of 17 ps under pump power of 24 W [15], in which a long silica fiber was applied to guide the signal output of the OPO back to meet the requirement of the synchronization. Also in 2010, another PPMgLN-based OPO driven by 20.8 ps pump pulses at 81.1 MHz was demonstrated [16], providing 7.1 W of signal at 1.56 m and 4.6 W of idler at 3.33 m for 16 W of pump power. Using a harmonic cavity, ps pulses with energies as high as 1.5 J in the mid-IR were reported at 1 MHz repetition rate [17].…”