Fiber-laser-pumped, high-power, continuous-wave, singly-resonant optical parametric oscillator based on MgO:sPPLT

摘要

High-power, continuous-wave (cw) mid-infrared optical parametric oscillators (OPOs) are of prime interest for variety of applications including spectroscopy and trace gas detection, requiring wide tunability and narrow linewidth. Singly-resonant OPOs (SROs) based on quasi-phase-matched(QPM) nonlinear materials such as MgO:PPLN represent the most viable configuration for such applications, because of high output power and simplified tuning. However, overcoming detrimental thermal effects is still a challenge [1]. The emergence of new QPM ferroelectric materials such as MgO-doped stoichiometric periodically-poled LiTaO3 (MgO:sPPLT), with improved optical and thermal properties [2], has lead to very important advances [3]. Also, cw SROs based on MgO:sPPLT, pumped in the green, have been previously demonstrated [3,4]. In spite of a lower effective nonlinear coefficient (deff∼9 pm/V) than PPLN (deff∼16 pm/V), increased resistance to photorefractive damage and better thermal conductivity in MgO:sPPLT make it an attractive new alternative to overcome performance limitations due to thermal effects. Hence, it would be of great interest to explore the feasibility of using MgO:sPPLT in cw SROs pumped at 1064 nm, for the generation of high optical powers in the mid-infrared.