Patent ID: 7515777

Claim:
An integrated electro-optic circuit comprising: one or more electro-optic semiconductor devices, each of the electro-optic semiconductor devices having an active region including one or more semiconductor quantum well structures, each of the semiconductor quantum well structures comprising: a well layer having a composition Si 1-x Ge x , wherein x is greater than about 0.7 and is selected such that an energy-momentum relation E w (k) of the lowest energy conduction band of the well layer at k=0 has a local minimum at k=0; a first barrier layer having a composition Si 1-y Ge y and disposed on a first side of the well layer, wherein y<x; and a second barrier layer having a composition Si 1-z Ge z and disposed on a second side of the well layer opposite the first side, wherein z<x; one or more optical waveguides optically coupled to one or more of the electro-optic semiconductor devices; and a device substrate, wherein the optical waveguides and the electro-optic semiconductor devices are integrated on the device substrate; wherein, for each of the electro-optic semiconductor devices, an electric field responsive to an input to the electro-optic device is present in the active region of the electro-optic semiconductor device; whereby, for each of the electro-optic semiconductor devices, an optical response of the electro-optic semiconductor device is altered by the input.