Efficient single-frequency pulsed PPLN optical parametric oscillator

Summary form only given. The attributes of periodically poled lithium niobate (PPLN) have enabled the development of efficient high repetition rate pulsed optical parametric oscillators (OPOs) driven by diode-pumped solid state lasers. These all-solid-state devices are attractive for remote sensing applications, but for sensing techniques such as DIAL and for many spectroscopic applications, narrowband or single frequency pulsed operation is required. In contrast to CW and long pulse OPOs, single frequency nanosecond OPOs require both a stable single-frequency pump laser and a technique for narrowing the OPO bandwidth. Passive line-narrowing (diffraction gratings and etalons) and injection seeding techniques have been widely used in critically phase matched OPOs, and injection-seeding has recently been implemented in a PPLN OPO driven by a lamp-pumped Nd:YAG laser at 10 Hz. However, to our knowledge, passive line-narrowing has not been implemented in PPLN, and narrowband 5 kHz operation has not been reported. Here we report the efficient line narrowing of a PPLN OPO using a single intracavity etalon. Single frequency operation at repetition rates of up to 5 kHz is demonstrated.