[摘要]：Two asynchronous, broadband 3.3 mu m pulse trains with a stabilized repetition-rate difference of up to 5 kHz were generated using an ultrafast optical parametric oscillator. The two oscillation channels, each producing similar to 100 mW average power, ran essentially independently, and weak non-phase-matched sum-frequency mixing between them provided a timing signal that indicated when the asynchronous pulses coincided. The system has immediate applications in incoherent asynchronous optical sampling and, with additional carrier-envelope-offset stabilization, could be applied to coherent dual-frequency-comb spectroscopy. (C) 2012 Optical Society of America
