| 摘要 |
PURPOSE:To obtain a face type optical gate which the wavelength range of usable light is wide by providing an incidence face and an exit face so that they form acute angles to the boundary surface between a quantum well layer and a high-refractive index semiconductor layer. CONSTITUTION:A quantum well layer 12 where a well layer 121 and a barrier layer 122 are alternately laminated on a substrate 11 and a GaAs high-refractive index semiconductor layer 13 laminated on the quantum well layer 12 are provided. In this case, the high-refractive index semiconductor layer 13 is provided with a face 14, on which a signal light 16 is made incident, and a face 15 from which the signal light 16 made incident on this incidence face 14 is emitted after being reflected on the boundary surface between the quantum well layer 12 and the high-refractive index semiconductor layer 13, and the incidence face 14 and the exit face 15 form acute angles to this boundary surface. Since the change of the critical angle due to the change of the refractive index of a quantum well is used, the wavelength range of light applicable to this optical gate is wider than that of a conventional optical gate. |
