Waveguide-based optical parametric chirped-pulse oscillator

A waveguide-based optical parametric chirped-pulse oscillator (OPCPO) enabling flexible spectral bandwidth control of the output pulses is demonstrated. Synchronously pumped by a mode-locked fiber laser with a fixed spectral bandwidth of 2.65 nm, the output idler spectral bandwidth was flexibly tunable between 0.7 and 14.4 nm at around 1.12 μm center wavelength by exclusively varying the pump pulse chirp using cavity-external grating-based pulse stretchers. Moreover, this bandwidth control was maintained across the idler wavelength tuning range, spanning at least 22 nm centered around 1.12 μm, with a maximum output idler energy of 337 pJ. This flexible output bandwidth control offers a degree of freedom for tailoring pulse properties without additional cavity modifications, enabling both broadband and narrowband applications with a single optical parametric oscillator.