Patent ID: 6895148

Claim:
An optical apparatus comprising: a first strip loaded waveguide; a second strip loaded waveguide; a semiconductor strip loaded waveguide that forms a resonant cavity providing an optical path between said first and second strip loaded waveguides which couples light between said first and second strip loaded waveguides, said semiconductor strip loaded waveguide forming said resonant cavity comprising a strip portion and a slab portion electrically isolated from each other by an insulator, at least one of said strip portion and said slab portion comprising semiconductor; and first and second electrodes electrically contacting said strip portion and slab portion, respectively, said first and second electrodes for applying an electric field through said insulator between said strip portion and said slab portion of said semiconductor strip loaded waveguide, the adjustment of said electric field changing free carrier density in said optical path such that absorption of light in said optical path is modified to decrease the coupling of light between said first and second strip loaded waveguides.