An optical modulating device may include a plurality of quantum dot (QD)-containing layers having QDs and a plurality of refractive index change layers. The QD-containing layers may be disposed between the refractive index change layers, respectively. The optical modulating device may be configured to modulate light-emission characteristics of the plurality of QD-containing layers. At least two of the QD-containing layers may have different central emission wavelengths. At least two of the plurality of refractive index change layers may include different materials or have different carrier densities.

The present invention has an object to provide an optical modulator having a small-sized circuit configuration and a smaller voltage drop amount in a terminating resistor. An optical modulator includes first and second optical waveguides, a first signal electrode that inputs a first high frequency signal into the first optical waveguide, a second signal electrode that inputs a second high frequency signal having a reverse phase with respect to a phase of the first high frequency signal into the second optical waveguide, a first terminating resistor connected to the first signal electrode at a terminating part side, a second terminating resistor connected to the second signal electrode at a terminating part side, a connection point that connects the first and second signal electrodes via the first and second terminating resistors, and a direct current voltage supply connected to the connection point. A resistance value of the first terminating resistor is equal to characteristic impedance of the first signal electrode. A resistance value of the second terminating resistor is equal to characteristic impedance of the second signal electrode.

A light modulation element constituted by a substrate type optical waveguide has a Mach-Zehnder interferometer; and a traveling wave electrode having a signal electrode arranged at least between a first phase modulator and a second phase modulator and electrically connected to both of the first phase modulator and the second phase modulator. A polarity of a semiconductor region of the first phase modulator connected to the signal electrode and a plurality of a semiconductor region of the second phase modulator connected to the signal electrode are different from each other.

A photon source device includes a substrate and a first waveguide arranged on the substrate. The first waveguide is coupled with a first pair of reflectors defining a first resonant cavity in the first waveguide. The first resonant cavity is configured for outputting a first output wavelength and a second output wavelength. The first pair of reflectors include a partial reflector for the first output wavelength and a partial reflector for the second output wavelength. The photon source device further includes a second pair of reflectors defining a second resonant cavity that intersects with the first resonant cavity. The second resonant cavity is configured for receiving an input wavelength distinct from the first and the second output wavelengths. A first reflector and a second reflector of the second pair of reflectors have a first reflectance and a second reflectance for the input wavelength, respectively.

Techniques regard electro-optic modulators are provided. For example, one or embodiments described herein can regard an apparatus that can comprise a first lateral region, a second lateral region, and a central region located on a semiconductor substrate. The first lateral region can be adjacent to a first side of the central region and can have a first conductivity type. The second lateral region can be adjacent to a second side of the central region and can have a second conductivity type. Also, the first side can be opposite to the second side. Further, the central region can comprise a diode junction adjacent to an intrinsic region. The intrinsic region can separate the first lateral region and the second lateral region.

Electro-optical modulators and methods of fabrication are disclosed. An electro-optical modulator includes a Mach-Zehnder interferometer containing an intrinsic silicon layer semiconductor layer and a coplanar waveguide. Signals from the coplanar waveguide are capacitively coupled to the Mach-Zehnder interferometer through first and second dielectric layers.

Ring modulators based on interdigitated junctions may be driven in full or partial standing wave mode and, active regions (providing the modulation) and light-absorptive regions (e.g. providing electrical conduction) are placed in a pattern inside a resonant cavity in order to match the maxima and minima of the optical field, respectively. The pattern may be periodic to match the periodicity of a typical electromagnetic field which is periodic with the wavelength. It may also be aperiodic in the case that the cross-section or materials are engineered along the direction of propagation such that the propagation constant (and thus wavelength, i.e. optical wave local periodicity) change along the propagation direction.

The object of the invention is a phase modulator including a modulation guide intended to guide die propagation of a light flow, said guide comprising a PN junction extending mainly along the main axis of propagation according to an oscillating continuous function. Advantageously, the oscillating continuous function is defined in such a way that the PN junction covers at least 50% of the light flow between the input and the output of the modulation guide. According to one possibility, the continuous function is sinusoidal. The object of the invention is also a switch and an intensity modulator each comprising a phase modulator.

A photonic chip. In some embodiments, the photonic chip includes a waveguide; and an optically active device comprising a portion of the waveguide. The waveguide may have a first end at a first edge of the photonic chip; and a second end, and the waveguide may have, everywhere between the first end and the second end, a rate of change of curvature having a magnitude not exceeding 2,000/mm.sup.2.

Systems and methods are described herein for an electro-absorption modulator (EAM) device. An example EAM device comprises an optical waveguide comprising a waveguide core configured to facilitate propagation of an optical signal therethrough; a segmented structure comprising diode segments disposed on the waveguide; and a differential electrical transmission line operatively coupled to the diode segments. The electrical transmission line includes a first transmission rail and a second transmission rail, and the electrical transmission line is configured to facilitate propagation of an electrical signal therethrough. The EAM device is configured for operation by a differential radio frequency (RF) source that is configured to supply the electrical signal to the EAM device, and the EAM device is formed on a semi-insulating substrate.