| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical modulation waveguide with a GaN-based semiconductor optical waveguide, which is unlikely to cause an inter-valence electron absorption and an optical transmission loss.SOLUTION: The optical modulation waveguide is formed by sequentially stacking in a C-axis direction a substrate, a nitride-based semiconductor cladding layer, a nitride-based semiconductor core layer, a first nitride-based semiconductor cladding layer, a second nitride-based semiconductor cladding layer and a nitride-based semiconductor contact layer. The nitride-based semiconductor core layer has a bandgap smaller than and a refractive index larger than those of the nitride-based semiconductor cladding layer and the first nitride-based semiconductor cladding layer. The first nitride-based semiconductor cladding layer has a lattice constant larger than those of the nitride-based semiconductor core layer and the second nitride-based semiconductor cladding layer, and receives a compressive strain and has a positive crystal field splitting energy. |
