Patent ID: 6608945
Filing Date: 2003-08-19
Classification: B82Y,G02B,G02F,H01L

Abstract:
A self-aligned optical modulator that modulates an input optical signal in order to generate a modulated output optical signal, comprising:an optical modulator device including a waveguide, a first modulating electrode, a second modulating electrode, and a two-dimensional electron (hole) gas (2DEG) proximate the first modulating electrode, the waveguide includes an input port wherein the input optical signal is introduced into the waveguide, an output port wherein the modulated output optical signal exits the waveguide, and a region of modulating propagation constant disposed along a first length of the waveguide and between the input port and the output port, wherein the input optical signal is guided by total internal reflection in the waveguide, and the waveguide is formed at least in part from an active semiconductor; the first modulating electrode is positioned proximate a first surface of the region of modulating propagation constant and electrically separated from an active semiconductor; the second modulating electrode is in electrical contact with the active semiconductor and disposed on a first side of the region of modulating propagation constant; the two-dimensional electron (hole) gas (2DEG) proximate the first modulating electrode has a free carrier distribution that is formed on the first surface when a modulating voltage is applied between the first modulating electrode and the second modulating electrode, wherein modulation of the voltage by the optical modulation device causes a corresponding modulation of the free carrier distribution which, in turn, causes corresponding modulation of a propagation constant level in the region of modulating propagation constant; a first deflector that deflects light in a first lateral direction within the waveguide; a second deflector configured to deflect light in a second lateral direction towards the waveguide wherein the deflection of the first deflector or the second deflector acts to direct light approaching the region of modulating propagation constant towards the region of modulating propagation constant.