Injection locking is employed to narrow the spectrum linewidth of individual modes of an active mode-locked laser diode (ML-LD). The multiple modes of the injection-locked ML-LD lie over 3.0 THz with 25-GHz spacing at 30 dB down; their linewidth and stability, ~25 MHz, are nearly the same as those of the master laser. We also demonstrate the accurate frequency measurement of laser diodes stabilized to molecular (H<sup>13</sup>C <sup>15</sup>N ,<sup>13</sup>C<sub>2</sub>H <sub>2</sub>) absorption lines by use of the injection-locked ML-LD.
© 1997 Optical Society of America
Mitsuhiro Teshima, Masafumi Koga, and Kenji Sato, "Accurate frequency control of a mode-locked laser diode by reference-light injection," Opt. Lett. 22, 126-128 (1997)