Stable, high-power, continuous-wave, single-frequency optical parametric oscillator pumped by a frequency-doubled fiber laser

Continuous-wave (cw) singly-resonant optical parametric oscillators (SROs) represent versatile sources of widely tunable, high-power, single-frequency radiation in spectral regions inaccessible to lasers. Pumped at 1.064 µm, PPLN cw SROs can cover the 1–5 µm spectral range, but access to wavelengths ≪1 mm is precluded by photorefractive damage in PPLN. Due to its large photorefractive damage threshold at and relatively high nonlinearity (d
eff
∼10pm/V), MgO:sPPLT is an attractive alternative for frequency conversion below 1 µm. Recently, we demonstrated that by exploiting this material and pumping at 532 nm, we can achieve practical operation down to 850 nm [1], and as short as 425 nm in the blue [2]. Operation of these cw SROs was made possible only by deploying commercial, high-power, high-cost, frequency-doubled cw Nd:YVO
4
laser (Coherent, Verdi-10). Here, we demonstrate operation of such green-pumped cw SROs using a fiber-based laser pump source. To our knowledge, the first report of a cw SRO pumped by a fiber-laser-based pump source at 532 nm in the green.