Efficient, single-mode, visible and infrared periodically poled lithium niobate OPOs

Abstract

Summary form only. Periodically poled lithium niobate (PPLN) has recently emerged as an attractive material for high gain, low pulse energy OPOs for spectroscopy and DIAL remote sensing applications. In many cases, narrowband or single mode operation is required, but pulsed ns OPOs exhibit broad free-running optical bandwidths, especially when operating near degeneracy. We report on OPOs in a grazing incidence (GI) configuration. These devices generate efficient, single axial mode, near TEM/sub 00/ output and offer a number of advantages over recently reported single mode PPLN OPOs incorporating injection seeding or intracavity cavity etalons. The GI OPO is a simple, compact device capable of emitting single mode radiation throughout the full tuning range of the OPO. It dispenses with the cost, complexity and limited tuning of seeded systems. Intracavity cavity etalons tend to preclude simultaneous signal and idler output, as well as single mode operation close to degeneracy. In the GI cavity, high loss-which limits the performance of KTP and BBO GI OPO-is offset by the substantially higher gain in PPLN.