Abstract: To provide a photonic crystal semiconductor device which enables various kinds of optical devices having a photonic crystal structure which is readily formed using a semiconductor and a semiconductor manufacturing process, and a manufacturing method thereof. The object can be achieved by a photonic crystal structure, including a lower DBR layer 1, a core layer 2, an upper DBR layer 3, and a dielectric multilayer film 6 which are sequentially laminated from an n-InP substrate 11 side, a plurality of holes 9 formed in the direction of a film thickness in the core layer 2 and the upper DBR layer 3, and a line defect portion 10 with none of the plurality of holes formed therein and disposed between the plurality of holes 9, wherein the line defect portion 10 serves as an optical waveguide.

Abstract: A surface-emitting semiconductor laser (VCSEL) having a structure in which the single horizontal mode of high power is stably maintained, and an optical device including a light-source device having this surface-emitting semiconductor laser are provided. A scattering-loss-structure portion composed of a low refractive-index region is disposed around a main current path in a surface-emitting semiconductor laser, namely around a cavity structure portion; the low refractive-index region is disposed at intervals; and the shape of the tip portion opposing to the center portion is set to be a tapered shape, for example, at an acute angle. Accordingly, in the cavity structure portion, the loss of light-emitting laser of a high-order mode localized in the outer circumferential portion becomes large, so that a surface-emitting semiconductor laser that oscillates the single-mode laser with favorable performance is constructed.

Abstract: An optical delay element including a photonic crystal line defect optical waveguide is disclosed that has a large group refractive index and has small or nearly constant wavelength dispersion of the group refractive index in a wide wavelength region for practical use. The optical delay element includes a line defect optical waveguide formed in a photonic crystal structure, and the volume of the line defect optical waveguide is less than the volume of a single line defect optical waveguide. Thereby, the waveguide band of the line defect optical waveguide has two zero points in the third order dispersion curve of the line defect optical waveguide, and the sign of the third order dispersion curve is inverted near the zero points.

Abstract: To provide a photonic crystal semiconductor device which enables various kinds of optical devices having a photonic crystal structure which is readily formed using a semiconductor and a semiconductor manufacturing process, and a manufacturing method thereof. The object can be achieved by a photonic crystal structure, including a lower DBR layer 1, a core layer 2, an upper DBR layer 3, and a dielectric multilayer film 6 which are sequentially laminated from an n-InP substrate 11 side, a plurality of holes 9 formed in the direction of a film thickness in the core layer 2 and the upper DBR layer 3, and a line defect portion 10 with none of the plurality of holes formed therein and disposed between the plurality of holes 9, wherein the line defect portion 10 serves as an optical waveguide.

Abstract: An optical control element is disclosed that can be made small and has a low loss, and is able to provide group speed control and wavelength dispersion of short light pulses. The optical control element is formed from a photonic crystal, and includes a first portion having a first refraction index in the photonic crystal, a second portion having a second refraction index lower than the first refraction index, and a refraction-index-distributed type defect wave guide. A difference effective refraction indexes between the first portion and the second portion near the refraction-index-distributed type defect wave guide, changing continuously or stepwise along a wave guiding direction of the refraction-index-distributed type defect wave guide.

Abstract: An optical control element is disclosed that can be made small and has a low loss, and is able to provide group speed control and wavelength dispersion of short light pulses. The optical control element is formed from a photonic crystal, and includes a first portion having a first refraction index in the photonic crystal, a second portion having a second refraction index lower than the first refraction index, and a refraction-index-distributed type defect wave guide. A difference effective refraction indexes between the first portion and the second portion near the refraction-index-distributed type defect wave guide, changing continuously or stepwise along a wave guiding direction of the refraction-index-distributed type defect wave guide.