| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor laser, which can easily control the output wavelength.SOLUTION: A semiconductor laser element 1A includes: a light emission end facet 4a; an optical waveguide 3 that includes a ring resonator 20 and whose one end is optically coupled to the light emission end facet 4a; N of gain waveguides 5 that generate light by current injection; an optical coupler 10e that optically couples the other end of the optical waveguide 3 to each one of the N of gain waveguides 5; and N of optical waveguides 6 that are optically coupled with the other ends of the N of gain waveguides 5 and on each of which a diffraction grating is formed. The center wavelengths of respective reflection wavelength bands of the diffraction gratings, each formed on the N of optical waveguides 6, are different from one another. |
