Thermal tuning of an optical device

An optical device, comprising:

• a substrate;
• an intermediate layer deposited on the substrate;
• a semiconductor layer, deposited on the intermediate layer, that includes a thermally tunable optical waveguide;
• a top layer, deposited on the semiconductor layer, which includes vias from an upper surface of the top layer to a bottom surface of the top layer which is proximate to the semiconductor layer;
• and
• electrodes, deposited on the top layer and in the vias, which electrically couple to the semiconductor layer, wherein the electrodes configured to reduce heat flow in a plane of the optical waveguide along a direction approximately perpendicular to an axis of the optical waveguide.

An optical device, comprising:

• a substrate;
• an intermediate layer deposited on the substrate;
• a semiconductor layer, deposited on the intermediate layer, that includes a thermally tunable optical waveguide;
• a top layer, deposited on the semiconductor layer, which includes vias from an upper surface of the top layer to a bottom surface of the top layer which is proximate to the semiconductor layer;
• and
• electrodes, deposited on the top layer and the vias, which electrically couple to the semiconductor layer, wherein doping of the semiconductor layer in the optical device defines a heater that facilitates thermal tuning of the optical waveguide;
• and
• wherein the doping of the semiconductor layer in a central region of the optical waveguide is less than doping of the semiconductor layer in a lateral region surrounding the optical waveguide, thereby reducing optical losses in the optical waveguide.