A "dual", feed-forward + feed-back frequency control for efficient and convenient diode laser line narrowing

Michel Lintz (1) , Duy-Hà Phung (1) , Jean-Pierre Coulon (1) , Benoit Faure (2) , Thomas Leveque (2)

1 ARTEMIS - Astrophysique Relativiste Théories Expériences Métrologie Instrumentation Signaux
2 CNES - Centre National d'Études Spatiales [Toulouse]

DFB diode lasers have linewidths in the MHz range. Narrowing the linewidth can be obtained by locking the diode to a frequency discriminator (Michelson interferometer,...). But the lock bandwidth has to reach 10 MHz or higher. The current-to-frequency transfer function of DFB lasers is complex: thermal effects at low frequency, carrier physics at high frequency, and a [1MHz-20MHz] transition zone in which the phase and amplitude show variations that prevent from locking in the MHz range. Adding a phase modulator in feed-forward (FF) configuration allows convenient control of the laser frequency, in excess of 15MHz, and convenient+efficient line narrowing with commercial, off the shelf components of the telecom industry.

Mots clés: Feed-forward control; Feed-back control; Spectral narrowing

Mots clés: Correction prédictive; Asservissement; Affinement spectral

Domaines: Sciences de l'ingénieur [physics]

Michel Lintz, Duy-Hà Phung, Jean-Pierre Coulon, Benoit Faure, Thomas Leveque. A "dual", feed-forward + feed-back frequency control for efficient and convenient diode laser line narrowing. ICSO, International Conference on Space Optics, Oct 2016, Biarritz, France. , 2016. ⟨hal-01476870⟩