Maintaining Narrow Linewidths for Pulsed QCL Lasers in Gas Sensing Applications

Continuous wave (CW) operation is generally favored for spectroscopy applications that use quantum cascade lasers (QCLs) because it is associated with a narrower linewidth than pulsed operation. However, the large power consumption and temperature regulation systems required for CW lasers can strongly limit their use in real-world applications. Teissier demonstrates that the narrow laser linewidths suitable for gas sensing applications close to atmospheric pressure can also be easily achieved with pulsed sources operating between 10 to 17 µm. This is a specific attribute of QCLs operating at longer wavelengths with low current densities. It leads to a wider spectral coverage for a given QCL chip and facilitates its integration into a system.

About the presenter
Roland Teissier, Ph.D., is chief laser scientist at mirSense, as well as a research director at the French Research institute CNRS. He holds a doctorate in the physics of semiconductor heterostructures from Paris 6 University and has established several global benchmarks for quantum cascade laser performance.