An optoelectronic device and an array comprising a plurality of the same. The device(s) comprising: an optically active region with an electrode arrangement for applying an electric field across the optically active region; a first curved waveguide, arranged to guide light into the optically active region; and a second curved waveguide, arranged to guide light out of the optically active region; wherein the first curved waveguide and the second curved waveguide are formed of a material having a different band-gap from a band-gap of the optically active region, and wherein the overall guided path formed by the first curved waveguide, the optically active region and the second curved waveguide is U-shaped.

Optical modulators are described having a Mach-Zehnder interferometer and a pair of RF electrodes interfaced with the Mach-Zehnder interferometer in which the Mach-Zehnder interferometer comprises optical waveguides formed from semiconductor material. The optical modulator additionally comprises a plurality of phase shifters configured to interface with the plurality of interconnected optical waveguides such that at least one phase shifter of the plurality of phase shifters is interfaced with at least one optical waveguide of the plurality of interconnected optical waveguides. A phase shifter controller, including an energy source with a variable output controlled by the controller and a plurality of electrical connections connecting the energy source to each of the plurality of phase shifters, is also included. In various embodiments, the plurality of electrical connections are configured to provide approximately equal power to each of the phase shifting elements from the energy source.

An optical modulator includes: a waveguide made of semiconductor, a light being input to one of ends of the waveguide; and a first electrode provided on the waveguide and overlapping with a part of the waveguide, wherein the waveguide has a first region to a third region along a propagation direction of the light from the one of ends, wherein neither the first region nor a part of the second region on a side of the first region in the propagation direction overlaps with the first electrode, wherein the third region and a part of the second region on a side of the third region in the propagation direction overlap with the first electrode, wherein a second width of the second region is larger than a first width of the first region and a third width of the third region.

A method of manufacturing an electro-optically active device. The method comprising the steps of: etching a cavity on a silicon-on-insulator wafer; providing a sacrificial layer adjacent to a substrate of a lll-V semiconductor wafer; epitaxially growing an electro-optically active structure on the lll-V semiconductor wafer; etching the epitaxially grown optically active structure into an electro-optically active mesa; disposing the electro-optically active mesa in the cavity of the silicon-on-insulator wafer and bonding a surface of the electro-optically active mesa, which is distal to the sacrificial layer, to a bed of the cavity; and removing the sacrificial layer between the substrate of the lll-V semiconductor wafer and the electro-optically active mesa.

A cadmium free quantum dot including a semiconductor nanocrystal core and a semiconductor nanocrystal shell disposed on the core, wherein the quantum dot does not include cadmium and includes indium and zinc, the quantum dot has a maximum photoluminescence peak in a red light wavelength region, a full width at half maximum (FWHM) of the maximum photoluminescence peak is less than or equal to about 40 nanometers (nm), an ultraviolet-visible (UV-Vis) absorption spectrum of the quantum dot includes a valley between about 450 nm to a center wavelength of a first absorption peak, and a valley depth (VD) defined by the following equation is greater than or equal to about 0.2, a quantum dot polymer composite including the same, and a display device including the quantum dot-polymer composite:
(Abs.sub.first−Abs.sub.valley)/Abs.sub.first=VD.

A cadmium free quantum dot not including cadmium and including: a semiconductor nanocrystal core comprising indium and phosphorous, a first semiconductor nanocrystal shell disposed on the semiconductor nanocrystal core and comprising zinc and selenium, and a second semiconductor nanocrystal shell disposed on the first semiconductor nanocrystal shell and comprising zinc and sulfur, a composition and composite including the same, and an electronic device.

An optoelectronic device includes a silicon substrate, with a silicon waveguide layer disposed over the silicon substrate and including an optical waveguide. One or more through-silicon vias (TSVs) extend through the silicon substrate and contact the silicon waveguide layer. A III-V base layer is disposed over the silicon waveguide layer, and an optical amplifier is disposed on the III-V base layer and optically coupled to the optical waveguide.

A method of providing electrical isolation between subsections in a waveguide structure for a photonic integrated device, the structure comprising a substrate, a buffer layer and a core layer, the buffer layer being located between the substrate and the core and comprising a dopant of a first type, the first type being either n-type or p- type, the method comprising the steps of prior to adding any layer to a side of the core layer opposite to the buffer layer: selecting at least one area to be an electrical isolation region, applying a dielectric mask to a surface of the core layer opposite to the buffer layer, with a window in the mask exposing an area of the surface corresponding to the selected electrical isolation region, implementing diffusion of a dopant of a second type, the second type being of opposite polarity to the first type, and allowing the dopant of the second type to penetrate to the substrate to form a blocking junction.

An optoelectronic device and an array comprising a plurality of the same. The device(s) comprising: an optically active region with an electrode arrangement for applying an electric field across the optically active region; a first curved waveguide, arranged to guide light into the optically active region; and a second curved waveguide, arranged to guide light out of the optically active region; wherein the first curved waveguide and the second curved waveguide are formed of a material having a different band-gap from a band-gap of the optically active region, and wherein the overall guided path formed by the first curved waveguide, the optically active region and the second curved waveguide is U-shaped.

Provided is an optical modulator capable of effectively dispersing and releasing heat generated by termination resistors, improving the reliability of a termination substrate including the termination resistors, and reducing influence of heat on an optical waveguide. In an optical modulator including an optical waveguide substrate on which an optical waveguide is formed, a signal electrode is provided on the optical waveguide substrate for applying an electric field, a termination resistor terminating the signal electrode, and a termination substrate on which the termination resistor is disposed, at least a plurality of the termination resistors are provided for a single termination substrate, and for preventing heat generated by the termination resistor from being concentrated on a local portion in the termination substrate or conducted to the optical waveguide substrate, a ground electrode provided on the termination substrate and electrically connected to the termination resistor is formed to be thicker than 0.1 m.