A simple method for measuring the linewidth enhancement factor α of a semiconductor laser by optical injection locking is described. Without knowledge of the absolute values of detuning and the optical injection level, the value of α is evaluated from only changes in optical power in the stable optical injection-locking state. The value of α of a 0.83-μm channeled substrate planar laser is evaluated to be 2.65 ± 0.2. The measurement error of this method is also discussed.
© 1992 Optical Society of America
Original Manuscript: March 31, 1992
Published: August 15, 1992
Koichi Iiyama, Ken-ichi Hayashi, and Yoshio Ida, "Simple method for measuring the linewidth enhancement factor of semiconductor lasers by optical injection locking," Opt. Lett. 17, 1128-1130 (1992)