An optical modulator includes a first Radio Frequency (RF) line and a second RF line; an optical waveguide along a length of the modulator with an input and an output; and a plurality of segments along the length including a first set of segments, a single RF line crossing, and a second set of segments, wherein the first set of segments and the second set of segments have an inversion of their respective orientation at the RF line crossing, and wherein the RF line crossing is located off center relative to the plurality of segments, wherein each of the first RF line and the second RF line extend along the length and cross one another at the RF line crossing.

An optical modulator may include a lower waveguide, an upper waveguide, and a dielectric layer disposed therebetween. When a voltage potential is created between the lower and upper waveguides, these layers form a silicon-insulator-silicon capacitor (also referred to as SISCAP) guide that provides efficient, high-speed optical modulation of an optical signal passing through the modulator. In one embodiment, at least one of the waveguides includes a respective ridge portion aligned at a charge modulation region which may aid in confining the optical mode laterally (e.g., in the width direction) in the optical modulator. In another embodiment, ridge portions may be formed on both the lower and the upper waveguides. These ridge portions may be aligned in a vertical direction (e.g., a thickness direction) so that ridges overlap which may further improve optical efficiency by centering an optical mode in the charge modulation region.

A waveguide is coupled at both ends to a microring (MRR) modulator in order to form a Mach-Zehnder interferometer out of the resulting unit. The coupled waveguide can be modulated independently from the MRR modulator itself with either an in-resonance photoconductive heater or a geometrically suitable PN junction. During modulation with an applied voltage to the coupler, an independent modulation can be applied to the MRR in order to compensate for wavelength shifting. Ideal lengths for the coupler are identified, as well as a spiral configuration to reduce the coupler's footprint on a photonic integrated circuit. The resulting device has reduced cross-talk between channels of a cascaded MRR system. A second coupler can be coupled to each MRR symmetrically so as to reduce insertion losses, allowing for an increased weight range at the drop and through ports.

An electro-optical modulator assembly including a transistor including a gate, a drain, and a source disposed on a substrate, a photonic modulator including a first waveguide structure positioned between a first electrode and a second electrode, the photonic modulator being integrated with the transistor on the substrate, and a metal connection coupled between the drain of the transistor and one of the first and second electrodes of the photonic modulator.

An optical modulator includes multiple segments including modulator segments and a Radio Frequency (RF) crossing segment where RF lines extending a length of the modulator cross one another. The present disclosure includes optimization of one or more of a geometry of the RF crossing and a location of the RF crossing segment along the length. The geometry is selected so that the RF crossing segment appears as another segment having similar characteristics as modulator segments. The location of the RF crossing segment is selected to balance out fabrication error and phase efficiency.

An electro-optical modulator assembly including a transistor including a gate, a drain, and a source disposed on a substrate, a photonic modulator including a first waveguide structure positioned between a first electrode and a second electrode, the photonic modulator being integrated with the transistor on the substrate, and a metal connection coupled between the drain of the transistor and one of the first and second electrodes of the photonic modulator.

An optical modulator may include a lower waveguide, an upper waveguide, and a dielectric layer disposed therebetween. When a voltage potential is created between the lower and upper waveguides, these layers form a silicon-insulator-silicon capacitor (also referred to as SISCAP) guide that provides efficient, high-speed optical modulation of an optical signal passing through the modulator. In one embodiment, at least one of the waveguides includes a respective ridge portion aligned at a charge modulation region which may aid in confining the optical mode laterally (e.g., in the width direction) in the optical modulator. In another embodiment, ridge portions may be formed on both the lower and the upper waveguides. These ridge portions may be aligned in a vertical direction (e.g., a thickness direction) so that ridges overlap which may further improve optical efficiency by centering an optical mode in the charge modulation region.

An electro-optical modulator assembly including a transistor including a gate, a drain, and a source disposed on a substrate, a photonic modulator including a first waveguide structure positioned between a first electrode and a second electrode, the photonic modulator being integrated with the transistor on the substrate, and a metal connection coupled between the drain of the transistor and one of the first and second electrodes of the photonic modulator.

Embodiments herein describe reverse biasing one or more PIN junctions formed in at least one layer of a PSR. The resulting electric fields in the PIN junctions overlap with the optical path of the optical signal and sweep away photo-generated hole-electron free carriers away. That is, the electric fields in the PIN junctions remove the free carriers from the path of the optical signal and reduces the population of the free carriers, thereby mitigating the negative impact of free-carrier absorption (FCA).

Embodiments herein describe reverse biasing one or more PIN junctions formed in at least one layer of a PSR. The resulting electric fields in the PIN junctions overlap with the optical path of the optical signal and sweep away photo-generated hole-electron free carriers away. That is, the electric fields in the PIN junctions remove the free carriers from the path of the optical signal and reduces the population of the free carriers, thereby mitigating the negative impact of free-carrier absorption (FCA).