Slab-mode and polarization clean-up in silicon photonics

摘要

Disclosed are structures and methods directed to waveguide structures exhibiting improved device performance including improved attenuation of scattered light and/or transverse magnetic modes. In an illustrative embodiment according to the present disclosure, a rib waveguide structure including a rib overlying a slab waveguide (or superimposed thereon) is constructed wherein the slab waveguide is heavily doped at a distance from the rib which has a very low overlap with rib guided modes. Advantageously, such doping may be of the P-type or of the N-type, and dopants could be any of a number of known ones including—but not limited to—boron, phosphorous, etc.—or others that increase optical propagation loss. As may be appreciated, the doped regions advantageously absorb scattered light which substantially improves the structures' performance.

主权项

1. A rib waveguide structure comprising:
a slab waveguide; and a rib formed upon a top surface of the slab waveguide, wherein the rib is configured to support a TE0 mode of light, wherein the slab waveguide includes a first doped region and a second doped region not contacting the rib, wherein the first doped region and the second doped region are spaced from the rib such that the rib waveguide structure is fully transparent to the TE0 mode of light, andwherein the first doped region and the second doped region are spaced from the rib such that the rib waveguide structure is absorptive of a TM0 mode of light.