A Mach-Zehnder modulator for modulating optical signals, and comprising: a plurality of modulating waveguide sections; at least one bias electrode in electrical communication with at least one modulating waveguide section and configured to apply at least one electrical bias signal to one or more of the modulating waveguide sections; and an output optical combiner comprising a plurality of inputs and a plurality of outputs, wherein the plurality of inputs of the combiner are in optical communication with output sides of the plurality of modulating waveguide sections, and wherein a plurality of the outputs of the combiner are monitor outputs.

An optical device may include at least two waveguides with different propagation constants. Each waveguide is associated with a grating antenna with a grating period selected to emit light at the same emission angle despite the different propagation constants. Each waveguide may be part of an optical path that includes phase shifters. Additionally, the waveguides may be formed in a waveguide layer that is separate from a perturbation layer in which the grating antennas as formed.

An optical waveguide modulator with automatic bias control is disclosed. A portion of the modulator light is mixed with reference light and converted to one or more electrical feedback signals. An electrical feedback circuit controls the modulator bias responsive to the feedback signals.

A photonic chip includes:a waveguide layer;one or two Mach-Zehnder modulators formed on and/or in the waveguide layer, comprising a first branch and a second branch, the branches being arranged between an optical input and an optical output in such a way that a light ray injected at the optical input is divided into a first ray and a second ray, which are then recombined at the optical output, each modulation branch being configured to modulate the phase of a light ray. The photonic chip further comprises at least two semiconductor optical amplifiers that are arranged so as to separately amplify the first ray and the second ray before they are recombined at the optical output.

An optical modulator includes an optical splitter splitting input optical signals into a first optical signal and a second optical signal and transmitting the first optical signal and the second optical signal to a first optical waveguide and a second optical waveguide, respectively, an optical combiner generating an output optical signal by combining the first and second optical signals transmitted from the first and second optical waveguides respectively, and including three output ports including a main output port, a first auxiliary output port, and a second auxiliary output port, three output optical waveguides connected to the three output ports, respectively, and transmitting the output optical signal, and an optical detector connected to at least one of the three output optical waveguides.

A Mach-Zehnder modulator for modulating optical signals, and comprising: a plurality of modulating waveguide sections; at least one bias electrode in electrical communication with at least one modulating waveguide section and configured to apply at least one electrical bias signal to one or more of the modulating waveguide sections; and an output optical combiner comprising a plurality of inputs and a plurality of outputs, wherein the plurality of inputs of the combiner are in optical communication with output sides of the plurality of modulating waveguide sections, and wherein a plurality of the outputs of the combiner are monitor outputs.

An optical phase shifter may include a waveguide core that has a top surface, and a semiconductor contact that is laterally displaced relative to the waveguide core and is electrically connected to the waveguide core. A top surface of the semiconductor contact is above the top surface of the waveguide core. The waveguide core may include a p-type core region and an n-type core region. A p-type semiconductor region may be in physical contact with the n-type core region of the waveguide core, and an n-type semiconductor region may be in physical contact with the p-type core region of the waveguide core. A phase shifter region and a light-emitting region may be disposed at different depth levels, and the light-emitting region may emit light from a phase shifter region that is in a position adjacent to the light-emitting region.

An apparatus is provided. The apparatus may include a drive circuit that selectively supplies a first plurality of electrical signals and a second plurality of electrical signals to a modulation circuit. Based on the first plurality of electrical signals, the modulation circuit may output a first in-phase component being modulated in accordance with a first tone having a first frequency and a first quadrature component being modulated in accordance with a second tone having a second frequency different than the first frequency. Based on the second plurality of electrical signals, the modulation circuit may output a second optical signal having a second in-phase component being modulated in accordance with the second tone and a second quadrature component being modulated in accordance with the first tone.

A photonic circuit with at least one nonlinear amplitude thresholder for correcting errors produced by linear photonic logic. One or more photonic input gates of the photonic circuit receive one or more input signals and generate one or more photonic signals based on the one or more photonic input signals. A first set of one or more photonic gates of the photonic circuit generates one or more intermediate photonic signals based on the one or more photonic signals. The at least one nonlinear amplitude thresholder generates at least one photonic thresholding signal based on the one or more intermediate photonic signals, the at least one nonlinear amplitude thresholder operating in a first operating regime, second operating regime, and/or third operating regime. A second set of one or more photonic gates of the photonic circuit generates one or more photonic output signals based on the at least one photonic thresholding signal.

An optical modulator includes an optical splitter splitting input optical signals into a first optical signal and a second optical signal and transmitting the first optical signal and the second optical signal to a first optical waveguide and a second optical waveguide, respectively, an optical combiner generating an output optical signal by combining the first and second optical signals transmitted from the first and second optical waveguides respectively, and including three output ports including a main output port, a first auxiliary output port, and a second auxiliary output port, three output optical waveguides connected to the three output ports, respectively, and transmitting the output optical signal, and an optical detector connected to at least one of the three output optical waveguides.