| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an electricity absorption type optical modulator which has a sufficient band gap and prevents positive holes from being piled up to enable large-light-quantity modulation and high-speed operation. <P>SOLUTION: The electricity absorption type optical modulator is formed of a compound semiconductor in layer structure comprising an n-clad layer, a modulation layer, a spacer layer, and a p-clad layer such that the energy difference between valence band ends of two adjacent layers is adjusted; and the spacer layer has as a component a group III element adjusting the electron affinity of layers, and the composition of the group III element is so selected thatΔEv=ΔEg-Δχ, whereΔEv is a specification value of the energy difference between the valence band ends,ΔEg is the difference in bang gap between the two adjacent layers, andΔEχis the difference in electron affinity. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
