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arXiv · 2203.08536

Spatially multiplexed single-cavity dual-comb laser

J. Pupeikis·B. Willenberg·S. L. Camenzind·A. Benayad·P. Camy·C. R. Phillips·U. Keller
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Abstract

Single-cavity dual-comb lasers are a new class of ultrafast lasers which have a wide possible application space including pump-probe sampling, optical ranging, and gas absorption spectroscopy. However, to this date laser cavity multiplexing usually came to the trade-off in laser performance or relative timing noise suppression. We present a new 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 Watts 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 new multiplexing technique, we could implement slow feedback on the repetition rate difference Δfrep, enabling this quantity to be drift-free, low-jitter, and adjustable - a key combination for practical applications that was lacking in prior single-cavity dual-comb systems.

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J. Pupeikis, B. Willenberg, S. L. Camenzind, A. Benayad, P. Camy, C. R. Phillips, U. Keller. 2022-06-27. Spatially multiplexed single-cavity dual-comb laser. https://doi.org/10.1364/optica.457787

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