Semiconductor optical modulator
US5521742A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 14, 1994 |
| Grant date | May 28, 1996 |
| Priority date | — |
| Expiry date | Mar 14, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F77/146
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A semiconductor optical modulator includes a light absorbing layer having a multi-quantum well structure including two quantum wells including quantum well layers bounded and separated by barrier layers, the quantum wells having respective, different .DELTA.Ev/.DELTA.Ec ratios where .DELTA.Ec is the discontinuity between the barrier layer and a quantum well layer in the conduction band edge and .DELTA.Ev is the discontinuity between the barrier layer and a quantum well layer in the valence band edge. By this construction, the absorption peak when no electric field is applied significantly shifts toward the longer wavelength side, resulting in a large difference between the absorption peak wavelength when no electric field is applied and the absorption peak wavelength when an electric field is applied, whereby the absorption loss of a semiconductor optical modulator when no electric field is applied is reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.