| 摘要 |
An external-cavity mode-locked semiconductor laser includes: a semiconductor laser device including a gain region and a saturable absorption region; a reflecting mirror; and a modulation bias generating circuit for supplying a modulation bias modulated by a microwave to the saturable absorption region. The semiconductor laser device has a reflecting surface and an output surface which faces the reflecting surface. The reflecting mirror is provided to face the output surface such that the reflecting surface and the reflecting mirror constitute a cavity. By using a cavity length L and an effective refractive index n of the cavity, a fundamental mode-locked frequency f<SUB>ML </SUB>is defined by the equation: f<SUB>ML</SUB>=c/2nL. A frequency of the microwave is M times the fundamental mode-locked frequency f<SUB>ML</SUB>. By using an effective refractive index n<SUB>D </SUB>of the semiconductor laser device and a device length L<SUB>D</SUB>, a frequency f<SUB>D </SUB>is defined by the equation: f<SUB>D</SUB>=c/2nL. The frequency f<SUB>D </SUB>is substantially coincident with the frequency of the microwave.
|
