A planar nematic liquid crystal (NLC) cell is incorporated into a Littman-type external cavity as the wavelength-tuning device for a semiconductor laser diode. By varying the driving voltage of the NLC cell and laser diode bias current simultaneously, we demonstrate single-mode oscillation and mode-hop-free tuning over 19.2 GHz at 775 nm. The result is in good agreement with the theoretical predictions.
© 2004 Optical Society of America
(140.0140) Lasers and laser optics : Lasers and laser optics
(140.3570) Lasers and laser optics : Lasers, single-mode
(140.3600) Lasers and laser optics : Lasers, tunable
(140.5960) Lasers and laser optics : Semiconductor lasers
(160.3710) Materials : Liquid crystals
Yu-Ping Lan, Ru-Pin Pan, and Ci-Ling Pan, "Mode-hop-free fine tuning of an external-cavity diode laser with an intracavity liquid crystal cell," Opt. Lett. 29, 510-512 (2004)