ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, 08860 Castelldefels, Barcelona, Spain.
Opt Lett. 2012 Jan 1;37(1):115-7. doi: 10.1364/OL.37.000115.
We demonstrate a novel technique for the generation of mode-locked pulses from a continuous-wave (cw) optical parametric oscillator (OPO). The technique is based on the deployment of a phase modulator in combination with an antiresonant ring interferometer internal to a cw OPO, simultaneously providing spectral broadening and phase-to-amplitude feedback modulation. The scheme is implemented in a doubly-resonant cw OPO based on MgO:sPPLT, configured in a standing-wave cavity and pumped at 532 nm. With the phase modulator activated and the cavity length synchronized, a stable train of 800 ps pulses is generated at a repetition rate of 160 MHz. Using single-pass second harmonic generation (SHG) of the OPO output, we observe a four times enhancement in SHG compared with cw operation, confirming the real achievement of energy concentration as a result of mode-locked operation.
我们展示了一种从连续波（cw）光参量振荡器（OPO）产生锁模脉冲的新方法。该技术基于在连续波 OPO 内部部署相位调制器和反共振环干涉仪，同时提供光谱展宽和相位到振幅反馈调制。该方案在基于 MgO：sPPLT 的双共振 cw OPO 中实现，采用驻波腔配置并在 532nm 处泵浦。在激活相位调制器并同步腔长的情况下，在 160MHz 的重复率下产生稳定的 800ps 脉冲序列。通过 OPO 输出的单次通过二次谐波产生（SHG），我们观察到与连续波操作相比，SHG 增强了四倍，这证实了由于锁模操作而实现的能量集中。
