Logo du site
  • English
  • Français
  • Se connecter
Logo du site
  • English
  • Français
  • Se connecter
  1. Accueil
  2. Université de Neuchâtel
  3. Publications
  4. Linewidth of a quantum cascade laser assessed from its frequency noise spectrum and impact of the current driver
 
  • Details
Options
Vignette d'image

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

Auteur(s)
Tombez, Lionel 
Institut de physique 
Schilt, Stephane 
Institut de physique 
Di Francesco, Joab 
Institut de physique 
Di Domenico, Gianni 
Institut de physique 
Hofstetter, Daniel 
Institut de physique 
Thomann, Pierre 
Institut de physique 
Date de parution
2012-4-21
In
Applied Physics B: Lasers and Optics
Vol.
3
No
109
De la page
407
A la page
414
Résumé
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 2196.6 cm^−1 is used to convert the frequency fluctuations of the laser into intensity fluctuations that are spectrally analyzed. We evaluate the influence of the laser driver on the observed QCL frequency noise and show how only a low-noise driver with a current noise density below ≈1 nA/√Hz allows observing the frequency noise of the laser itself, without any degradation induced by the current source. We also show how the laser FWHM linewidth, extracted from the frequency noise spectrum using a simple formula, can be drastically broadened at a rate of ≈1.6 MHz/(nA/√Hz) for higher current noise densities of the driver. The current noise of commercial QCL drivers can reach several nA/√Hz , leading to a broadening of the linewidth of our QCL of up to several megahertz. To remedy this limitation, we present a low-noise QCL driver with only 350 pA/√Hz current noise, which is suitable to observe the ≈550 kHz linewidth of our QCL.
Lié au projet
Fundamental metrology with laser-cooled atoms and optical frequency combs 
Identifiants
https://libra.unine.ch/handle/123456789/17101
_
10.1007/s00340-012-5005-x
Autre version
http://link.springer.com/article/10.1007/s00340-012-5005-x
Type de publication
journal article
Dossier(s) à télécharger
 main article: 2014-04-28_850_2862.pdf (4.13 MB)
google-scholar
Présentation du portailGuide d'utilisationStratégie Open AccessDirective Open Access La recherche à l'UniNE Open Access ORCIDNouveautés

Service information scientifique & bibliothèques
Rue Emile-Argand 11
2000 Neuchâtel
contact.libra@unine.ch

Propulsé par DSpace, DSpace-CRIS & 4Science | v2022.02.00