Wavelength-tunable semiconductor laser and fabrication process thereof

摘要

A wavelength tunable semiconductor laser comprises an active region including an active layer generating an optical gain by injection of a current, a phase control region including a tuning layer generating variation of a refraction index by injection of the current, and a distributed Bragg reflector region including a tuning layer generating variation of a refraction index by injection of the current. The active region, the phase control region and the distributed Bragg reflector region are arranged in alignment in a resonance direction. A diffraction grating is provided in the vicinity of the tuning layer of the distributed Bragg reflector region. The wavelength tunable semiconductor laser includes means for uniformly injecting a current to the phase control region and the distributed Bragg reflector region. The optical confinement factor to the tuning layer of the phase control region is greater than an optical confinement factor to the tuning layer of the distributed Bragg reflector type. $$