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arXiv · 2412.16702

Highly coherent phase-lock of an 8.1 $\mu$m quantum cascade laser to a turn-key mid-IR frequency comb

B. Chomet·D. Gacemi·O. Lopez·L. Del Balzo·A. Vasanelli·Y. Todorov·B. Darquié·C. Sirtori
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Abstract

A continuous-wave Fabry-Perot quantum cascade laser (QCL) emitting at 8.1 $\mu$m operating in the single mode regime has been coherently phase locked to a turn-key low-noise commercial mid-Infrared (mid-IR) optical frequency comb. The stability of the comb used as a reference is transferred to the QCL resulting in an integrated residual phase error of 0.4 rad. The laser linewidth is narrowed by more than two orders of magnitude reaching sub-kHz level at 1 ms observation time, limited by the spectral purity of the mid-IR comb. Our experiment is an important step toward the development of both powerful and metrology-grade QCLs and fully stabilized QCL frequency comb and opens perspectives for precision measurements and frequency metrology in the mid-IR.

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B. Chomet, D. Gacemi, O. Lopez, L. Del Balzo, A. Vasanelli, Y. Todorov, B. Darquié, C. Sirtori. 2024-12-21. Highly coherent phase-lock of an 8.1 $\mu$m quantum cascade laser to a turn-key mid-IR frequency comb. https://doi.org/10.1063/5.0152013

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