Picosecond synchronously pumped optical parametric oscillator based on chirped quasi-phase matching

Abstract

We investigate and model a picosecond synchronously pumped optical parametric oscillator (OPO) based on an aperiodically poled lithium niobate (APPLN) nonlinear crystal with a chirped quasi-phasematching (QPM) grating. We observe remarkable spectral features with an asymmetric OPO spectrum consisting of a main peak with lower side-lobes. Depending on the sign of the QPM chirp rate, the sidelobes are located either on the red or on the blue side of the main peak. Meanwhile, side-bands develop in the depleted pump spectrum. We attribute these features to cascaded sum-/difference-frequency generation processes which are quasi-phase matched at different positions in the APPLN crystal. A terahertzgeneration cascading effect is also observed and characterized at high pump power.

Simultaneous oscillation of dual optical parametric oscillators on monolithic chi(2) nonlinear photonic crystals

“…Wavelength-tunable lasers based upon parametric down conversion and optical parametric oscillation (OPO) have been reported by using nonlinear optical (NLO) crystals and QPM NPCs [2,3]. Further, in the regime of multi-wavelengths OPO, Walter et al had studied the spectral dynamic behaviours on apodized aperiodically poled lithium niobate [4]. However, the latter spectra exhibited unequal power distribution because of gain competition and the cascaded effect in increasing the threshold for the second OPO.…”