Described are methods and a system for atomic memory operations with contended cache lines. A processing system includes at least two cores, each core having a local cache, and a lower level cache in communication with each local cache. One local cache configured to request a cache line to execute an atomic memory operation (AMO) instruction, receive the cache line via the lower level cache, receive a probe downgrade due to other local cache requesting the cache line prior to execution of the AMO, and send the AMO instruction to the lower level cache for remote execution in response to the probe downgrade.

A tunable laser for a transceiver includes a silicon photonics substrate, first and second patterned regions each being defined in the substrate a step lower than a flat surface region of the substrate, first and second laser diode chips arranged in the first and second patterned regions, the patterned regions being configured to align the gain regions of the first and second laser diode chips with integrated couplers formed in the substrate adjacent to the first and second patterned regions to facilitate flip-bonding the first and second laser diode chips within the patterned regions, and a tuning filter coupled to the first laser diode chip and the second laser diode chip via the integrated couplers. The tuning filter is configured to receive laser light from each of the first and second laser diode chips and generate a laser output having a gain determined by each of the gain regions.

A light emitting apparatus includes a laminated structure provided at a substrate and including a plurality of columnar sections. The plurality of columnar sections each includes a light emitting layer including a plurality of first well layers, a first semiconductor layer provided between the substrate and the light emitting layer and containing Ga and N, an optical confining layer provided between the first semiconductor layer and the light emitting layer and confining light in the light emitting layer, and a second well layer provided between the first semiconductor layer and the optical confining layer. The first well layers and the second well layer are made of InGaN. The optical confining layer includes an InGaN layer. The composition formula of the first well layers is In.sub.xGa.sub.1-xN. The composition formula of the InGaN layer of the optical confining layer is In.sub.yGa.sub.1-yN. The composition formula of the second well layer is In.sub.zGa.sub.1-zN. The parameters x, y, and z satisfy 0<y<z<x<1.

A light emitting apparatus includes a substrate and a laminated structure provided at a substrate surface of the substrate and including a plurality of columnar sections. The columnar sections each include a light emitting layer which has a first end facing the substrate and a second end facing away from the substrate. A first cross section of each of the columnar sections taken along the directions perpendicular to the lamination direction of the laminated structure includes the first end. A second cross section of each of the columnar sections taken along the directions perpendicular to the lamination direction is a cross section that is part of the light emitting layer and located at a position shifted from the first cross section toward the side away from the substrate in the lamination direction. In the plan view viewed in the lamination direction, the position of the center of the first cross section differs from the position of the center of the second cross section.

This application describes a wavelength-tunable laser apparatus, which reduces complexity of wavelength tuning of a laser. The laser includes a reflective gain unit, an optical phase shifter, a coupler, and a passive filter unit array. Furthermore, an output port of the reflective gain unit is connected to an input port of the optical phase shifter, an output port of the optical phase shifter is connected to an input port of the coupler, a first output port of the coupler is connected to an input port of the passive filter unit array, and a second output port of the coupler is an output port of the laser. The passive filter unit array includes a plurality of passive filter units, where any two of the plurality of passive filter units have different wavelength tuning ranges, and each filter unit has a linearly tunable wavelength.

Disclosed is a laser device. The laser device includes a substrate, a pump light source which is disposed on the substrate and provided with a light emitting layer configured to generate pump light, and an upper waveguide which is disposed above the pump light source in a first direction and provided with an upper resonator configured to allow laser light to be generated and resonate by using the pump light.

The light emitting device includes a substrate, and a laminated structure including columnar parts, wherein the columnar parts include a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, and a light emitting layer disposed between the first semiconductor layer and the second semiconductor layer, the light emitting layer has a c-plane and a facet plane, the second semiconductor layer is disposed on the c-plane and the facet plane, the first semiconductor layer has a first portion and a second portion smaller in diametrical size than the first portion, the second portion is disposed between the substrate and the first portion, and the c-plane and the second portion overlap each other, and the c-plane is smaller in diametrical size than the second portion in a plan view from a stacking direction of the first semiconductor layer and the light emitting layer.

A light-emitting device assembly includes an emitter array of light-emitting elements, a transparent substrate, a structured lens, and an angular filter. The emitter array emits from its emission surface output light that is transmitted through the substrate, and enables selective activation of and emission from individual elements or subsets of elements of the array. The structured lens is formed on or in the substrate, and comprises micro- or nano-structured elements resulting in an effective focal length less than an effective distance between the structured lens and the emission surface. The angular filter is positioned on or in the substrate or on the emission surface and exhibits decreasing transmission or a cutoff angle with increasing angle of incidence.

The disclosure provides a nanolaser based on a depth-subwavelength graphene-dielectric hyperbolic dispersive cavity, comprising a pumping light source and the depth-subwavelength graphene-dielectric hyperbolic dispersive cavity; wherein the depth-subwavelength graphene-dielectric hyperbolic dispersive cavity is a spherical or hemispherical hyperbolic dispersive microcavity formed by alternately wrapping a dielectric core with graphene layers and dielectric layers. Because the graphene plasmon has unique excellent performances, such as an electrical adjustability, a low intrinsic loss, a high optical field localization, and a continuously adjustable resonance frequency from mid-infrared to terahertz, compared with a common metal-dielectric hyperbolic dispersive characteristic, a graphene-dielectric hyperbolic dispersive metamaterial used by the disclosure not only may highly localize an energy of an electromagnetic wave in a more depth-subwavelength cavity, but also may reduce an ohmic loss and improve a quality factor.

A light emitting device includes a substrate, and a laminated structure provided to the substrate, and including a columnar part, wherein the columnar part includes a first GaN layer having a first conductivity type, a second GaN layer having a second conductivity type different from the first conductivity type, and a light emitting layer disposed between the first GaN layer and the second GaN layer, the first GaN layer is disposed between the substrate and the light emitting layer, the light emitting layer has a first well layer as an InGaN layer, the first GaN layer has a c-face region, the first GaN layer has a crystal structure of a cubical crystal, and has a first layer constituting the c-face region, and a second layer as a GaN layer having a crystal structure of a hexagonal crystal is disposed between the first layer and the first well layer.