Spectroscopic Characterization of Narrowband Output from Injection-Seeded Pulsed Optical Parametric Oscillators

Abstract

Pulsed optical parametric oscillators (OPOs) are versatile nonlinear-optical (NLO) sources of tunable coherent light for spectroscopic sensing applications. One of our most recent demonstrations of such OPO wavelength control strategies is a novel self-adaptive tunable (SAT) design, in which a photorefractive crystal serves as a phase-conjugate cavity mirror and enables SLM tuning without active variation of OPO cavity length as the TDL seed wavelength λseed is scanned. We now report further details of the performance of such a SAT OPO, including narrowband spectroscopic characteristics of its idler output at λidler, via cavity ringdown absorption spectra of CO2(g) at ∼1.44 μm, and of its seeded signal output at λsignal, by recording fluorescence-detected Doppler-free two-photon absorption (TPA) spectra of Cs(g) at ∼822 nm.