Coherence analysis of tightly locked mid-infrared quantum cascade laser frequency combs

Abstract

Frequency combs are powerful tools for many applications and high performances are achieved by stabilizing these lasers. For operation in the mid-infrared, quantum cascade lasers (QCL) are ideal candidates as they present numerous advantages. However, stabilized QCL-combs lack of a detailed characterization of their noise properties due to the sensitivity limits of current analyzing techniques. To overcome these challenges, we developed what we believe to be the first tightly locked dual QCL-comb system. Its use is twofold. First, phase noise analysis of the dual-comb signal shows residual phase noise below 600 mrad for all comb lines, and we characterize the comb coherence as well as the performances of the repetition frequency locking mechanism. Second, we demonstrate coherent averaging with a $7\times 10^5$ Hz${}^{1/2}$ figure-of-merit system, which is compatible with high precision spectroscopy.

References in corpus (13)

• Frequency comb spectroscopy
• Spectroscopy of the Methane ν3 Band with an Accurate Mid-Infrared Coherent Dual- Comb Spectrometer
• Cavity-enhanced optical frequency comb spectroscopy in the mid-infrared - application to trace detection of H2O2
• Quantum cascade laser frequency stabilisation at the sub-Hz level
• Coherent injection locking of quantum cascade laser frequency combs
• A phase-stable dual-comb interferometer
• Computational coherent averaging for free-running dual-comb spectroscopy
• Fully phase-stabilized quantum cascade laser frequency comb
• High-resolution and gapless dual comb spectroscopy with current-tuned quantum cascade lasers
• High-precision methanol spectroscopy with a widely tunable SI-traceable frequency-comb-based mid-infrared QCL
• Intrinsic linewidth of quantum cascade laser frequency combs
• Mid-infrared quantum cascade laser frequency combs with a microstrip-like line waveguide geometry
• Coherent Control of Mid-Infrared Frequency Comb by Optical Injection of Near-Infrared Light

Cited by in corpus (2)

• Near-to mid-IR spectral purity transfer with a tunable frequency comb: methanol frequency metrology over a record frequency span
• Non-resonant Optical Injection Locking in Quantum Cascade Laser Frequency Combs