Patent ID: 7203403

Claim:
An optical switching apparatus, comprising: first and second waveguides; a carrier controlled optical switch having at least first and second states, said carrier controlled optical switch comprising: (i) a coupling waveguide which provides an optical path between said first and second waveguides, said coupling waveguide comprising a substantially annular shaped strip and a substantially disc shaped slab positioned proximate the annular shaped strip, said annular shaped strip and said disc shaped slab comprising semiconductor material, at least one of said annular shaped strip and said disc shaped slab having a refractive index dependent on a distribution of free carriers therein; and (ii) first and second electrodes electrically connected to said annular shaped strip and said disc shaped slab, respectively, to apply an electric field through the semiconductor material in said annular shaped strip and said disc shaped slab, wherein said distribution of free carriers is responsive to application of said electric field to change the state of said carrier controlled optical switch from said first state to said second state.