| 摘要 |
PURPOSE:To make it possible to perform operation at a single wavelength and to make it possible to perform operation at a fundamental lateral mode and at a low threshold current value, by forming a diffraction grating on an InP substrate, and surrounding an active layer with a medium having a low refractive index. CONSTITUTION:A diffraction grating 11 is formed on the main surface of an InP substrate 10. On the grating 11, a waveguide layer 12 comprising N-type GaInAsP, a current blocking layer 16 comprising P-type InP and a current blocking layer 17 comprising N-type InP are sequentially laminated and formed. On an active layer 13 and the blocking layer 17, a clad layer 14 comprising P-type InP and a cap layer 15 comprising P-type GaInAsP are sequentially laminated and formed so as to bury a groove 18. Thus, single-wavelength operation is made possible, and operation at a fundamental lateral mode and at a low threshold current value is made possible. |
