title: Broadband, high-power, continuous-wave, mid-infrared source using extended phase-matching bandwidth in MgO:PPLN.
abstract: We report a compact and viable source of broadband, high-power, cw, mid-IR radiation based on a singly resonant optical parametric oscillator (SRO) pumped by a wide-bandwidth cw Yb fiber laser centered at 1060 nm. By exploiting the extended phase-matching bandwidth in a 50 mm crystal of MgO:PPLN and a ring SRO cavity, we obtain 5.3 W of broadband idler output for 25.5 W of pump at >80% depletion, transferring a pump bandwidth of 73.9 cm(-1) to an idler spectrum spread across an equal bandwidth centered at 3454 nm. By deploying output coupling of the signal, we generate 11.2 W of total power at 44% extraction efficiency with a pump depletion of >73% at the maximum available pump power. Measurements of transverse modal power confirm Gaussian distribution of signal and idler beams.
authors.affiliation: ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, 08860 Castelldefels, Barcelona, Spain. ritwick.das@icfo.es
authors.forename: Ritwick
authors.initials: R
authors.lastname: Das
authors.forename: S Chaitanya
authors.initials: SC
authors.lastname: Kumar
authors.forename: G K
authors.initials: GK
authors.lastname: Samanta
authors.forename: M
authors.initials: M
authors.lastname: Ebrahim-Zadeh