Method and system for a silicon-based optical phase modulator with high modal overlap

A system for communication, the system comprising:

• a rib waveguide having, in a cross-sectional plane perpendicular to a light path of the rib waveguide, a cross-shaped depletion region and four alternately doped sections separated by the cross-shaped depletion region, wherein the four alternately doped sections comprise a shallow depth p-region, a shallow depth n-region, a deep p-region, and a deep n-region, and wherein the shallow depth p-region is electrically coupled to the deep p-region periodically along a length of the rib waveguide where the shallow depth p-region extends across a width of the rib waveguide, the rib waveguide being operable to:
• receive an optical signal at one end of the rib waveguide;
• and
• modulate the received optical signal by applying a modulating voltage to the rib waveguide.

A system for communication, the system comprising:

• a semiconductor die having a rib waveguide, the rib waveguide comprising:
• a slab section with a lower n-region and a lower p-region;
• a rib section on the slab section and comprising an upper n-region and an upper p-region;
• and
• a cross-shaped depletion region, in a cross-sectional plane perpendicular to a light path of the rib waveguide, the cross-shaped depletion region formed by the lower n- region, the lower p-region, the upper n-region, and the upper p-region, wherein the upper p-region is electrically coupled to the lower p-region periodically along a length of the rib waveguide where the upper p-region extends across a width of the rib waveguide.

A method for optical communication, the method comprising:

• in a waveguide having, in a cross-sectional plane perpendicular to a light path of a rib waveguide, a cross-shaped depletion region and four alternately doped sections separated by the cross-shaped depletion region, wherein the four alternately doped sections comprise a shallow depth p-region, a shallow depth n-region, a deep p-region, and a deep n-region, and wherein the shallow depth n-region is electrically coupled to the deep n-region periodically along a length of the rib waveguide where the shallow depth n-region extends across a width of the rib waveguide:
• receiving an optical signal at one end of the rib waveguide;
• and
• modulating the received optical signal by applying a modulating voltage to the rib waveguide.

A system for communication, the system comprising:

• a rib waveguide having, in a cross-sectional plane perpendicular to a light path of the rib waveguide, a cross-shaped depletion region and four alternately doped sections separated by the cross-shaped depletion region, wherein the four alternately doped sections comprise a shallow depth p-region, a shallow depth n-region, a deep p-region, and a deep n-region, and wherein the shallow depth n-region is electrically coupled to the deep n-region periodically along a length of the rib waveguide where the shallow depth n-region extends across a width of the rib waveguide, the rib waveguide being operable to:
• receive an optical signal at one end of the rib waveguide;
• and
• modulate the received optical signal by applying a modulating voltage to the rib waveguide.