Transient dynamics in a common singly resonant optical parametric oscillator

Abstract

The dynamics of a common optical parametric oscillator (OPO) is demonstrated for the first time with dispersive Fourier transform (DFT) technique. The singly resonant MgO:PPLN-based optical parametric oscillator is synchronously pumped with an Yb-doped fiber amplifier, and delivers a femtosecond signal wave with a spectrum tuned from 1284 to 1517 nm. Then a DFT device is built and the birth and extinction dynamics of the single- and dual-wavelength signal wave of the OPO is recorded. Compared with conventional mode-locked lasers, the dynamics evolution of the OPO is entirely attributed to the nonlinear effects in the nonlinear crystal different from the atomic transitions in the active media, which gives rise to novel features in the starting progress of the OPO. Furthermore, a new way of energy transfer is discovered for the first time during the evolution of dual-wavelength signal wave. The results are believed to provide a unique insight into evolution in OPOs and are instructive for in-depth understanding of OPO and other nonlinear devices and materials.