QCL-based frequency metrology from the mid-infrared to the THz range: a review
QCL-based frequency metrology from the mid-infrared to the THz range: a review
Quantum cascade lasers (QCLs) are becoming a key tool for plenty of applications, from the mid-infrared (mid-IR) to the THz range. Progress in related areas, such as the development of ultra-low-loss crystalline microresonators, optical frequency standards, and optical fiber networks for time and frequency dissemination, is paving the way for …