Patent ID: 7260281

Claim:
An optical isolator, comprising: first and second optical splitter-combiners disposed within a semiconductor die; first and second waveguide sections disposed within the semiconductor die coupling the first and second optical splitter-combiners in an interferometer configuration; and a non-reciprocal optical phase shift element disposed within the semiconductor die, the first waveguide section passing through the non-reciprocal optical phase shift element, wherein a forward propagating wave is constructively recombined by the second optical splitter-combiner while a reverse propagating wave is destructively recombined by the first optical splitter-combiner, wherein the non-reciprocal optical phase shift element comprises: a first contact magnetized in a first direction disposed adjacent to a first side of the first waveguide section to polarize spins of first charge carriers injected into the first waveguide section; and a second contact magnetized in a second direction substantially opposite the first direction disposed adjacent to a second side of the first waveguide section to oppositely polarize spins of second charge carriers injected into the first waveguide section.