Abstract: A nitride-based light-emitting device includes, on a GaN substrate: a first-conductivity-side first semiconductor layer; an active layer; and a second-conductivity-side first semiconductor layer, in the stated order, and further includes an electron barrier layer of a second conductivity type between the active layer and the second-conductivity-side first semiconductor layer, the electron barrier layer including a nitride-based semiconductor containing at least Al. The electron barrier layer has a first region in which an Al composition changes. The Al composition in the first region monotonically increases in a direction from the active layer to the second-conductivity-side first semiconductor layer. An impurity concentration in the second-conductivity-side first semiconductor layer is lower in a region nearer the electron barrier layer than in a region farther from the electron barrier layer.

Abstract: A fiber laser apparatus includes a pumping light source which launches pumping light, an amplifying optical fiber which includes a core and a noncircular cladding, and absorbs the pumping light to launch laser light, an amplifying coil which has a configuration around which the amplifying optical fiber is wound, a first reflector which is provided on an input side of the amplifying coil and is configured to reflect the laser light toward the amplifying coil, and a second reflector which is provided on a launching side of the amplifying coil, has a lower reflectance than a reflectance of the first reflector, and is configured to reflect the laser light toward the amplifying coil.

Abstract: Gallium and nitrogen containing optical devices operable as laser diodes are disclosed. The devices include a gallium and nitrogen containing substrate member, which may be semipolar or non-polar. The devices include a chip formed from the gallium and nitrogen substrate member. The chip has a width and a length. The devices have a cavity oriented substantially parallel to the length of the chip, a dimension of less than 120 microns characterizing the width of the chip, and a pair of etched facets configured on the cavity of the chip. The pair of etched facets includes a first facet configured at a first end of the cavity and a second facet configured at a second end of the cavity.

Abstract: A damping circuit having an input terminal and an output terminal is described. The damping circuit comprises a driver having an input and an output; an RC circuit coupled between the input terminal and the output; and a resistor coupled between the output and the output terminal, wherein the RC circuit delays passing a signal from the output terminal to the input terminal and a low impedance associated with the driver generally reduces ringing.

Abstract: An optical apparatus comprises an optical resonator defining an optical resonator path for an optical resonator beam and an optical beam expander optically coupled to the optical resonator, the optical beam expander defining an optical beam expander path for an optical beam expander beam. The optical resonator path and the optical beam expander path may be configured such that the optical resonator beam and the optical beam expander beam at least partially intersect. Such an optical apparatus may be configured for use as a laser target designator or a laser range finder.

Abstract: A multilayer device includes a substrate and a first layer disposed on the substrate. A trench extends through one or both of the substrate and the first layer. The trench has a first sidewall spaced apart from a second sidewall, each sidewall extending from an upper surface of the substrate to a lower surface of the first layer. An optically active region is disposed on the first layer overlying the trench, such that at least a portion of the optically active region is located within a set of lines corresponding to the sidewalls of the trench.

Abstract: A movable diffraction grating includes: a support portion; a movable portion swingably connected to the support portion; a coil buried in the movable portion; a magnetic field generator configured to apply a magnetic field to the coil; an insulation layer provided on a surface of the movable portion; a resin layer provided on the insulation layer and provided with a diffraction grating pattern; and a reflection layer formed of a metal and provided on the resin layer to follow the diffraction grating pattern.

Abstract: A complementary metal oxide semiconductor (CMOS) vertical transistor structure with closely spaced p-type and n-type vertical field effect transistors (FETs) is provided. After forming a dielectric material portion contacting a proximal sidewall of a first semiconductor fin for formation of a p-type vertical FET and a proximal sidewall of a second semiconductor fin for formation of an n-type vertical FET, a first gate structure is formed contacting a distal sidewall of the first semiconductor fin, and a second gate structure is formed contacting a distal sidewall of the second semiconductor fin. Because no gate structures are formed between the first and second semiconductor fins, the p-type vertical FET is spaced from the n-type FET only by the dielectric material portion.

Abstract: A QCL may include a substrate, an emitting facet, and semiconductor layers adjacent the substrate and defining an active region. The active region may have a longitudinal axis canted at an oblique angle to the emitting facet of the substrate. The QCL may include an optical grating being adjacent the active region and configured to emit one of a CW laser output or a pulsed laser output through the emitting facet of substrate.

Abstract: An Nd3+ optical fiber laser and amplifier operating in the wavelength range from 1300 to 1450 nm is described. The fiber includes a rare earth doped optical amplifier or laser operating within this wavelength band is based upon an optical fiber that guides light in this wavelength band. The waveguide structure attenuates light in the wavelength range from 850 nm to 950 nm and from 1050 nm to 1150 nm.

Abstract: A QCL (10) includes a first electrode (15), a first contact layer (11) that is in contact with the first electrode (15) and is made of a first compound semiconductor, a second electrode (14) having a polarity opposite to that of the first electrode (15), a second contact layer (13) that is in contact with the second electrode (14) and is made of a second compound semiconductor, and an active layer (12) disposed between the first contact layer (11) and the second contact layer (13) and including two or more active layer units. Each of the active layer units includes one or more quantum well layers made of a third compound semiconductor and one or more barrier layers made of a fourth compound semiconductor, and each of the quantum well layers and each of the barrier layers are alternately stacked.

Abstract: A quantum cascade laser includes a semiconductor substrate and an active layer having a cascade structure, in which unit layered bodies, each composed of a quantum well light emitting layer and an injection layer, are stacked, wherein the unit layered body has a subband level structure having an upper laser level, a lower laser level, and a relaxation miniband composed of at least two energy levels with an energy spacing smaller than the energy difference (EUL) between the upper laser level and the lower laser level, the energy width of the relaxation miniband is smaller than the energy (ELO?EUL) obtained by subtracting the energy difference (EUL) from the energy (ELO) of longitudinal optical phonons, and electrons subjected to the intersubband transition are relaxed in the relaxation miniband and are injected into a quantum well light emitting layer in a subsequent unit layered body.

Abstract: A dielectric electrode assembly, and a method of manufacture thereof, including: a dielectric tube having a cylindrical cross-section and a relative dielectric constant, ?2, the dielectric tube filled with a gas having a relative dielectric constant, ?1; a structural dielectric having a relative dielectric constant, ?3 surrounding the dielectric tube; metal electrodes on opposite sides of the structural dielectric, the metal electrodes having a flat cross-sectional geometry; and the structural dielectric made from a material selected such that the relative dielectric constants of the structural dielectric, the dielectric tube, and the gas are interrelated and a uniform electric field is generated within the dielectric tube when power is applied to the metal electrodes.

Abstract: A method for patterning a sequence of layers and a semiconductor laser device are disclosed. In an embodiment the method creates at least one trench in the sequence of layers by two plasma etching methods. The semiconductor laser device comprises a sequence of layers including a semiconductor material and two trenches in the sequence of layers. The trenches laterally delimit a ridge waveguide. Each of the trenches is delimited on the side facing away from the ridge waveguide by a region of the sequence of layers.

Abstract: The disclosure relates to a fin field effect transistor (FinFET) formed in and on a substrate having a major surface. The FinFET includes a fin structure protruding from the major surface, which fin includes a lower portion, an upper portion, and a middle portion between the lower portion and upper portion, wherein the fin structure includes a first semiconductor material having a first lattice constant; a pair of notches extending into opposite sides of the middle portion; and a semiconductor liner adjoining the lower portion. The semiconductor liner is a second semiconductor material having a second lattice constant greater than the first lattice constant.

Abstract: A laser component has a housing, which includes a carrier having a cavity with a bottom surface and a sidewall, wherein the cavity widens starting from the bottom surface, the side wall is inclined relative to the bottom surface by an angle different from 45°, a laser chip, an emission direction of which is oriented parallel to the bottom surface, is arranged on the bottom surface in the cavity, a reflective element is arranged in the cavity and bears on an edge between the bottom surface and the side wall, a reflective surface of the reflective element defines an angle with the bottom surface of the cavity, and the emission direction defines an angle of 45° with the reflective surface of the reflective element.

Abstract: Provided herein are methods of fabricating a magnetic memory device including forming magnetic tunnel junction patterns on a substrate, forming an interlayered insulating layer on the substrate to cover the magnetic tunnel junction patterns, forming a conductive layer on the interlayered insulating layer, patterning the conductive layer to form interconnection patterns electrically connected to the magnetic tunnel junction patterns, and performing a cleaning process on the interconnection patterns. The cleaning process is performed using a gas mixture of a first gas and a second gas. The first gas contains a hydrogen element (H), and the second gas contains a source gas different from that of the first gas.

Abstract: A laser using a laser diode and a narrow wavelength from a resonant atomic transition of a predetermined material. The gain range of the laser diode encompasses the wavelength of the resonant atomic transition. A vapor cell containing a material, such as a metal vapor, providing the resonant atomic transition forming the predetermined wavelength is placed between permanent magnets. In one embodiment the vapor cell has opposing windows positioned at a Brewster's angle and rotated 90° relative to each other. The laser produces a very narrow bandwidth of a predetermined wavelength with high power. The laser configuration eliminates several optical components reducing cost.

Abstract: A laser oscillator includes a discharge tube having a discharge area in which laser gas is excited and an output coupler and a rear mirror respectively arranged at both sides of the discharge tube. A first coating material having first reflectance is stacked as a dielectric multilayer on a first area including a radial center portion of a surface of the output coupler, which faces the discharge area, and a second coating material having second reflectance higher than the first reflectance is stacked as a dielectric multilayer on a second area around the first area.