| 摘要 |
PURPOSE:To provide the optical switch usable in a wide wavelength region by successively laminating a 1st clad layer of a 1st conduction type, an optical wave layer and a 2nd clad layer of a 2nd conduction type and forming the band gap of the optical wave guide layer to a double hetero-junction structure smaller than the band gap of the 1st clad layer and the 2nd clad layer. CONSTITUTION:This optical switch is made into the double hetero-structure laminated with the n-Al0.3GaAs0.7As clad layer 102, the GaAs guide 103, the p-Al0.3GaAs0.7As clad layer 104 and a p-GaAs gap layer 105 on an n-GaAs substrate 101. Signal light 111 is absorbed by the GaAs optical wave guide layer 103 while current is not made to flow between an Au-Zn alloy electrode 107 and an Au-Ge alloy electrode 106 and, therefore, output light 112 is shut off. Light emission is generated by the recombination of carriers while the current is made to flow and, therefore, the light loss in the GaAs optical wave guide layer 103 is negative. The optical switch which can be used in the wide wavelength region and has a sufficient extinction ratio and a low transmission loss characteristic in combination is obtd. in this way. |
