| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor laser device suitable for a forward excitation light source of a Raman amplifier. SOLUTION: The semiconductor laser device 100 comprises an active layer 45 of a multi-quantum well structure and separated confinement hetero structure (SCH) layers 42, 44, 50, and 52 formed over and below the active layer 45. A clad layer 16 is formed on the top face of the SCH layer 52 located in the most upper layer. At an interface between the SCH layer 52 and the clad layer 16, a uniform diffraction grating 36 is formed over the entire length of the active layer 45. The semiconductor laser device has a normalized coefficient of coupling of 0.8 or below. Since the semiconductor laser device performs multi-mode lasing, the output light is hardly scattered in an optical fiber. The semiconductor laser device has a low RIN and has a superior wavelength stabilization. COPYRIGHT: (C)2003,JPO
|
