Single-cavity dual-comb lasers are a new class of ultrafast lasers that have a wide possible application space including pump–probe sampling, optical ranging, and gas absorption spectroscopy. However, to date, laser cavity multiplexing has usually come with a trade-off in laser performance or relative timing noise suppression. We present a method for multiplexing a single laser cavity to support a pair of noise-correlated modes. These modes share all intracavity components and take a near-common path, but do not overlap on any active elements. We implement the method with an 80-MHz laser delivering more than 2.4 W of average power per comb with sub-140-fs pulses. We reach sub-cycle relative timing jitter of 2.2 fs [20 Hz, 100 kHz]. With this multiplexing technique, we can implement slow feedback on the repetition rate difference Δfrep$\Delta\!{{ f}_{{\rm rep}}}$, enabling this quantity to be drift-free, have low jitter, and be adjustable—a key combination for practical applications that was lacking in prior single-cavity dual-comb systems.

中文翻译：

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空间复用单腔双梳激光器

单腔双梳激光器是一类新型超快激光器，具有广泛的应用空间，包括泵浦-探针采样、光学测距、气体吸收光谱等。然而，迄今为止，激光腔多路复用通常伴随着激光性能或相对时序噪声抑制的权衡。我们提出了一种复用单个激光腔以支持一对噪声相关模式的方法。这些模式共享所有腔内组件并采用近乎共同的路径，但不会在任何活动元件上重叠。我们使用 80-MHz 激光器实​​施该方法，每梳子的平均功率超过 2.4 W，脉冲低于 140-fs。我们达到了 2.2 fs [20 Hz, 100 kHz] 的子周期相对时序抖动。使用这种复用技术，我们可以实现对重复率差异的慢反馈Δf r e p$\Delta\!{{ f}_{{\rm rep}}}$，使该数量无漂移、低抖动且可调节——这是先前单腔双梳系统所缺乏的实际应用的关键组合。