| 摘要 |
<p>A semiconductor optical device having a refractive index changed responsive to irradiation of an incident optical beam comprises a first material layer (M1) having a first band gap (Eg1) and a first thickness (l1) set so as to allow existence of a two-dimensional exciton (LE) interacting with the incident optical beam, a second material layer (M2) having a second band gap (Eg2) substantially larger than the first band gap and disposed at both sides of the first material layer, the second material layer having a second thickness (l2) for allowing a tunneling of electron therethrough, and a third material layer (M3) having a third band gap (Eg3) substantially smaller than the second band gap and provided at least on one side of the second material layer, the third material layer having a third thickness (l3) set such that there are formed one or more quantum levels of electron (L3) all of which being energetically different from at least one of those (L1) formed in the first material layer.</p> |
