Quantum well optical waveguide phase shifter
US5811830A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 8, 1995 |
| Grant date | Sep 22, 1998 |
| Priority date | — |
| Expiry date | Jun 8, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/01708
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention is achieved by layering a dielectric slab between a ground plane and a two dimensional quasi quantum well heterostructure and by switching between an unbiased state and a negative potential which is established between the quantum well heterostructure and the ground plane. In the unbiased state, the device supports wave propagation in the dielectric with a phase velocity similar to that of a wave propagating in a parallel plate waveguide. Upon application of the bias voltage, that is establishing a negative potential difference between contacts based on either side of the quantum well heterostructure, the conductivity of the quantum well decreases. Therefore, as the carrier wave propagates the wave interacts with a boundary similar to that of a dielectric-air interface. This new boundary condition, in turn, produces a faster phase velocity. Hence, toggling the bias modulates the quantum well conductivity which changes the phase velocity of the carrier wave.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.