Abstract: A laser includes an active region surrounded by first and second waveguide layers. Two or more mask openings are formed within a dielectric layer on a surface parallel to the active region. A refractive grating is formed on the dielectric mask openings and includes three-dimensional grating features spaced apart in the light-propagation direction of the laser. The refractive grating provides modulation of a real part of the effective refractive index of the laser and modulation of the imaginary part is provided by modulation of the current flow through the mask openings.

Abstract: In various embodiments, emitter modules include a laser source and (a) a refractive optic, (b) an output coupler, or (c) both a refractive optic and an output coupler. Either or both of these may be situated on mounts that facilitate two-axis rotation. The mount may be, for example, a conventional, rotatively adjustable “tip/tilt” mount or gimbal arrangement. In the case of the refractive optic, either the optic itself or the beam path may be adjusted; that is, the optic may be on a tip/tilt mount or the optic may be replaced with two or more mirrors each on tip/tilt mount.

Abstract: A photonic chip includes an optical layer bonded, at a bonding interface, to an interconnection layer, the thickness of the optical layer being smaller than 15 ?m, a primary via that extends through the interconnection layer solely between a lower face and the bonding interface, an electrical terminal chosen from the group consisting of an electrical contact embedded in the interior of the optical layer and of an electrical track produced on an upper face, a second via that extends the primary via into the interior of the optical layer in order to electrically connect the primary via to the electrical terminal, this secondary via extending in the interior of the optical layer from the bonding interface to the electrical terminal, the maximum diameter of this secondary via being smaller than 3 ?m.

Abstract: An object is to improve the efficiency of amplification by rare earth ion while maintaining beam quality of output light in a multi-mode fiber doped with rare earth ion. A multi-mode fiber (11) that includes a rare-earth-ion-doped core and that has a normalized frequency of not less than 2.40 includes a filter portion (111) that is formed by bending a partial section of or entirety of the multi-mode fiber (11), the filter portion (111) having a smallest diameter (diameter R1) that is set so that (1) only LP01, LP11, LP21, and LP02 modes propagate or only LP01 and LP11 modes propagate and (2) a loss of a highest-order one of the modes that propagate is not more than 0.1 dB/m.

Abstract: An optical fiber, such as in some instances a high-power, diode-pumped, dual-clad, ytterbium-doped fiber amplifier (YDFAs), having a fundamental mode and at least one higher order mode, wherein the higher order mode or modes have mode areas that are substantially larger than a mode area of the fundamental mode.

Abstract: Embodiments are directed to the fabrication of an electro-optical device. The device comprises the forming of an active region with a stack of III-V semiconductor gain materials stacked along a stacking direction z. The active region may be formed as a slab having several lateral surface portions, each extending parallel to the stacking direction z. The device further comprises selectively re-growing two paired elements, which include: a pair of doped layers of III-V semiconductor materials (an n-doped layer and a p-doped layer); and a pair of lateral waveguide cores. The two paired elements may be laterally arranged, two-by-two, on opposite sides of the slab. The elements distinctly adjoin respective ones of the lateral surface portions of the slab, so as for these elements to be separated from each other by the slab. The disclosure may be further directed to related silicon photonics devices.

Abstract: A pulsed laser device includes a laser light source, an electro-optic modulator, a laser light source driver, an electro-optic modulator driver, and a controller to control the laser light source driver and the electro-optic modulator driver. The laser light source outputs pulsed laser light pulse-modulated by the laser light source driver. The electro-optic modulator outputs pulsed laser light obtained by causing the electro-optic modulator driver to pulse-modulate the pulsed laser light from the laser light source. The control unit controls the laser light source driver and the electro-optic modulator driver such that the electro-optic modulator turns on at least while the laser light source is on and the electro-optic modulator turns on at least once while the laser light source is off, thereby increasing a duty ratio of the pulse modulation for the electro-optic modulator relative to a duty ratio of the pulse modulation for the laser light source.

Abstract: A method of semiconductor fabrication includes forming a dielectric layer over a substrate. A dummy gate structure is formed on the dielectric layer, which defines a dummy gate dielectric region. A portion of the dielectric layer not included in the dummy gate dielectric region is etched to form a dielectric etch back region. A spacer element is formed on a portion of the dielectric etch back region, which abuts the dummy gate structure, and defines a spacer dielectric region A height of the dummy gate dielectric region is greater than the height of the spacer dielectric region. A recessed portion is formed in the substrate, over which a strained material is selectively grown to form a strained recessed region adjacent the spacer dielectric region. The dummy gate structure and the dummy gate dielectric region are removed. A gate electrode layer and a gate dielectric layer are formed.

Abstract: A broad area quantum cascade laser includes an optical cavity disposed between two sidewalls, the optical cavity including an active region for producing photons when a current is applied thereto, where the optical cavity is subject to a presence of at least one high order transverse optical mode due to its broad area geometry. The broad area quantum cascade laser may also include an optically lossy material disposed on at least a first portion of one or more of the two sidewalls.

Abstract: A system for producing single-frequency or near-single-frequency operation of a laser beam includes a laser for emitting a laser beam at each one of a plurality of cavity lengths, A detector is configured to receive at least a portion of the laser beam emitted, and generate a signal. A computer system is configured to identify at least one beat note in the signal for each of at least one of the plurality of cavity lengths, the at least one beat note indicating the presence of one or more higher-order transverse modes, longitudinal modes, or both, in the received at least the portion of the laser beam emitted at the at least one of the plurality of cavity lengths. The cavity is adjusted to one of the plurality of cavity lengths for eliminating or minimizing the at least one beat note.

Abstract: A laser device that is easily assembled and can be manufactured at a low cost and a light-source device using the same are provided. The laser device includes a mount member including a mount surface, and a semiconductor laser element placed on the mount surface of the mount member. An upper side and lateral sides of the semiconductor laser element on the mount surface are exposed.

Abstract: A VCSEL device includes a substrate and a first DBR structure disposed on the substrate. The VCSEL device further includes a cathode contact disposed on a top surface of the first DBR structure. In addition, the VCSEL device includes a VCSEL mesa that is disposed on the top surface of the first DBR structure. The VCSEL mesa includes a quantum well, a non-circularly-shaped oxide aperture region disposed above the quantum well, and a second DBR structure disposed above the non-circularly-shaped oxide aperture region. In addition, the VCSEL mesa includes a selective polarization structure disposed above the second DBR structure and an anode contact disposed above the selective polarization structure.

Abstract: A high-power laser beam with an arbitrary intensity profile is produced. Such beam has a variety of uses including for laser materials processing such as powder bed fusion additive manufacturing. Several challenges in additive manufacturing are mitigated with the present non-uniform intensity laser profiles. Nonuniform shapes include a set of intensity pixels in a line that could print a wide stripe area instead of just a single line. One example uses the multimode interference pattern from the output of a ribbon fiber which is imaged onto a work piece. The interference pattern is controlled to allow turning on or off of ‘pixels’ along a line which can be used to shape the beam and form the additively manufactured part.

Abstract: A micro laser diode transfer method and a manufacturing method comprise: forming a bonding layer (515) on a receiving substrate (513), wherein first type electrodes (514) are connected to the bonding layer (515); bringing a first side of the micro laser diodes (500r) on a carrier substrate (520) into contact with the bonding layer (515), wherein the carrier substrate (520) is laser-transparent; and irradiating selected micro laser diodes (500r) with laser from the side of the carrier substrate (520) to lift-off the selected micro laser diodes (500r) from the carrier substrate (520). This method may improve yield.

Abstract: A light source device includes a substrate and a plurality of laser light sources. The laser light sources each include a submount mounted on the substrate, and a semiconductor laser element mounted on the submount. The laser light sources are individually and independently disposed on the substrate. The laser light sources disposed adjacent to each other and emitting light having an identical wavelength band differ from each other in thermal resistance at a region between the semiconductor laser element and the substrate.

Abstract: A light-emitting diode (LED) display panel includes a substrate, a driver circuit array on the substrate and including a plurality of pixel driver circuits arranged in an array, an LED array including a plurality of LED dies each being coupled to one of the pixel driver circuits, a micro lens array including a plurality of micro lenses each corresponding to and being arranged over at least one of the LED dies, and an optical spacer formed between the LED array and the micro lens array.

Abstract: The present disclosure is directed toward circuits for driving one or more laser diodes with a series of current pulses, where the energy required for each current pulse is generated and stored on a pulse-by-pulse basis. Laser-driver circuits in accordance with the present disclosure include a charge-storage inductor that is electrically coupled with a power supply and a charge-storage capacitor that is electrically coupled with a laser-diode string. The electrical coupling between the inductor and capacitor is controlled by one or more switches having on- and off-states that determine whether the inductor is charged by the power supply, charges the capacitor, or whether the charged capacitor generates a current pulse in the laser-diode string. By controlling the states of the switches, the energy provided to the laser-diode string can be controlled on a pulse-by-pulse basis.

Abstract: The laser apparatus includes a master oscillator, an amplifier, a power source, and a controller to control the power source. The controller controls the power source such that an excitation intensity of the amplifier in a burst oscillation period performing the burst oscillation is a first excitation intensity, controls the power source such that, if the predetermined repetition frequency is a first repetition frequency, an excitation intensity of the amplifier in a suspension period suspending the burst oscillation is a second excitation intensity equal to or lower than the first excitation intensity, and controls the power source such that, if the predetermined repetition frequency is a second repetition frequency higher than the first repetition frequency, the excitation intensity of the amplifier in the suspension period is a third excitation intensity lower than the second excitation intensity.

Abstract: In a method, energy is supplied to a first gas discharge chamber of a first stage until a pulsed amplified light beam is output from the first stage and directed toward a second stage. While the energy is supplied to the first gas discharge chamber: a value of an operating parameter of the first gas discharge chamber is measured; it is determined whether to adjust an operating characteristic of the first gas discharge chamber based on the measured value; and, the operating characteristic of the first gas discharge chamber is adjusted if it is determined that the operating characteristic of the first gas discharge chamber should be adjusted. After it is determined that the operating characteristic of the first gas discharge chamber no longer should be adjusted, then an adjustment procedure is applied to an operating characteristic of a second gas discharge chamber of the second stage.

Abstract: A vertical cavity light-emitting element comprises a substrate, a first multilayer reflector formed on the substrate, a semiconductor structure layer formed on the first multilayer reflector and including a light emitting layer, a second multilayer reflector formed on the semiconductor structure layer and constituting a resonator together with the first multilayer reflector, and a light guide layer configured to form a light guide structure including a center region extending in a direction perpendicular to the upper surface of said substrate between the first and second multilayer reflectors and including a light emission center of the light-emitting layer and a peripheral region provided around the center region and having a smaller optical distance between the first and second multilayer reflectors than that in the center region. The second multilayer reflector has a flatness property over the center region and the peripheral region.