Patent ID: 7711212
Filing Date: 2010-05-04
Classification: G02F

Abstract:
1. A method of modulating a light beam carrier signal, the method comprising: passing the light beam carrier signal though a waveguide with Junction Field Effect Transistor (JFET) formed therein, wherein the JFET comprises a gate, a drain, a source, and a drain to source conductive channel having a variable conductivity; passing a majority carrier bias current through the drain to source conductive channel; modulating the conductivity of the drain to source conductive channel using a gate electrode to receive a modulating signal; depleting a width of the drain to source conductive channel using a reverse bias voltage to form a depletion region; spatially modulating flow of current across the waveguide to change the degree of overlap between the waveguide mode and the free carrier distribution; and modulating a refractive index (Δn) across the waveguide by varying voltage at the gate to produce a modulated light beam carrier signal.