Université de Neuchâtel

Linewidth of a quantum cascade laser assessed from its frequency noise spectrum and impact of the current driver

Tombez, Lionel ; Schilt, Stéphane ; Di Francesco, Joab F. ; Führer, Thorsten ; Rein, Benjamin ; Walther, Thomas ; Di Domenico, Gianni ; Hofstetter, Daniel ; Thomann, Pierre

In: Applied Physics B : Lasers and optics, 2012, vol. 109, no. 3, p. 407-414

We report on the measurement of the frequency noise properties of a 4.6-μm distributed-feedback quantum-cascade laser (QCL) operating in continuous wave near room temperature using a spectroscopic set-up. The flank of the R(14) ro-vibrational absorption line of carbon monoxide at 2196.6cm−1 is used to convert the frequency fluctuations of the laser into intensity fluctuations that...