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arXiv · 1509.08856

Dispersion engineering of Quantum Cascade Lasers frequency combs

Gustavo Villares·Sabine Riedi·Johanna Wolf·Dmitry Kazakov·Martin J. Süess·Mattias Beck·Jérôme Faist
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Abstract

Quantum cascade lasers are compact sources capable of generating frequency combs. Yet key characteristics - such as optical bandwidth and power-per-mode distribution - have to be improved for better addressing spectroscopy applications. Group delay dispersion plays an important role in the comb formation. In this work, we demonstrate that a dispersion compensation scheme based on a Gires-Tournois Interferometer integrated into the QCL-comb dramatically improves the comb operation regime, preventing the formation of high-phase noise regimes previously observed. The continuous-wave output power of these combs is typically $>$ 100 mW with optical spectra centered at 1330 cm$^{-1}$ (7.52 $\mu$m) with $\sim$ 70 cm$^{-1}$ of optical bandwidth. Our findings demonstrate that QCL-combs are ideal sources for chip-based frequency comb spectroscopy systems.

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Gustavo Villares, Sabine Riedi, Johanna Wolf, Dmitry Kazakov, Martin J. Süess, Mattias Beck, Jérôme Faist. 2015-09-29. Dispersion engineering of Quantum Cascade Lasers frequency combs. https://arxiv.org/abs/1509.08856

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