A method and mode conversion waveguide system for converting a mode of a light is provided. The light is sent through a single mode waveguide, wherein the light has a first mode while traveling through single mode waveguide. The light is sent from the single mode waveguide into a multimode interference region having connected to the single mode waveguide. The light is reflected with a cavity within the multimode interference region in a manner that causes the light to propagate away from the single mode waveguide. The light is output from multimode interference region, wherein the light has a second mode.

One example LIDAR device comprises a substrate and a waveguide disposed on the substrate. A first section of the waveguide extends lengthwise on the substrate in a first direction. A second section of the waveguide extends lengthwise on the substrate in a second direction different than the first direction. A third section of the waveguide extends lengthwise on the substrate in a third direction different than the second direction. The second section extends lengthwise between the first section and the second section. The LIDAR device also comprises a light emitter configured to emit light. The waveguide is configured to guide the light inside the first section toward the second section, inside the second section toward the third section, and inside the third section away from the second section.

The subject matter of this specification can be implemented in, among other things, systems and methods of optical sensing that utilize optimized processing of multiple sensing channels for efficient and reliable scanning of environments. The optical sensing includes multiple optical communication lines that include coupling portions configured to facilitate efficient collection of various received beams. The optical sensing system further includes multiple light detectors configured to process collected beams and produce data representative of a velocity of an object that generated the received beam and/or a distance to that object.

A chip carrier socket for an electronic-photonic integrated-circuit (EPIC) assembly comprises a carrier bottom and a carrier top configured to mate to the carrier bottom while enclosing the EPIC assembly within an enclosed cavity. The carrier bottom comprises one or more conductive vias passing from a first surface of the carrier bottom to an opposite second surface of the carrier bottom, each conductive via providing electrical connectivity between an electrically conductive pad on the first surface of the carrier bottom and a respective electrically conductive pad, solder ball, or electrically conductive spring on the second surface of the carrier bottom. One or both of the carrier bottom and the carrier top comprises a fluid inlet port and a fluid outlet port. Further, either or both of the carrier bottom and the bottom top comprises an optical via passing from one surface to another of the carrier bottom or carrier top.

The invention refers to a photonic integrated circuit (PIC), the photonic integrated circuit comprising: at least one laser, the laser having a laser output, a measuring portion including a measuring port and configured to measure an intensity and/or wavelength of light input at the measuring port, and an output portion configured to output light from the photonic integrated circuit to the portion of the tissue, wherein optionally the laser includes a ring resonator laser, a laser generating light having a fixed wavelength, a laser being constructed using hybrid integration, and/or a tunable laser.

Structures for a cavity included in a photonics chip and methods of fabricating a structure for a cavity included in a photonics chip. The structure includes a substrate, a back-end-of-line stack having interlayer dielectric layers on the substrate, and a cavity penetrating through the back-end-of-line stack and into the substrate. The cavity includes first sidewalls and second sidewalls, and the second sidewalls have an alternating arrangement with the first sidewalls to define non-right-angle corners.

There is provided a method for fabricating a vertically tapered spot-size converter on a substrate, comprising: growing a waveguide core on the substrate; coating the waveguide core with a photoresist layer; placing a photomask having patterns at a negative focus offset point with respect to the photoresist layer, the patterns being defined by openings in the photomask, each opening having a cross-section comprising a region of constant width and at least one region of non-constant width, the non-constant width reducing in a direction extending away from the region of constant width; transferring the patterns of the photomask to the photoresist layer; providing the waveguide core with a vertically tapered profile, the vertically tapered profile being provided by the patterns of the photomask; growing a cladding layer over the waveguide core; and patterning and etching the cladding layer and the waveguide core, thereby defining the vertically tapered spot-size converter.

A semiconductor package includes a redistribution structure, a supporting layer, a semiconductor device, and a transition waveguide structure. The redistribution structure includes a plurality of connectors. The supporting layer is formed over the redistribution structure and disposed beside and between the plurality of connectors. The semiconductor device is disposed on the supporting layer and bonded to the plurality of connectors, wherein the semiconductor device includes a device waveguide. The transition waveguide structure is disposed on the supporting layer adjacent to the semiconductor device, wherein the transition waveguide structure is optically coupled to the device waveguide.

Structures for a wavelength division multiplexing filter and methods of fabricating a structure for a wavelength division multiplexing filter. The structure includes a first waveguide core having a first section and a second section. The first section and the second section have a first notched sidewall and a second notched sidewall opposite to the first notched sidewall. The structure further includes a second waveguide core positioned with a first offset in a first direction relative to the first section and the second section of the first waveguide core and with a second offset in a second direction relative to the first section and the second section of the first waveguide core. The second direction is transverse to the first direction.

Examples disclosed herein relate to quantum-dot (QD) photonics. In accordance with some of the examples disclosed herein, a QD semiconductor optical amplifier (SOA) may include a silicon substrate and a QD layer above the silicon substrate. The QD layer may include an active gain region to amplify a lasing mode received from an optical signal generator. The QD layer may have a gain recovery time such that the active gain region amplifies the received lasing mode without pattern effects. A waveguide may be included in an upper silicon layer of the silicon substrate. The waveguide may include a mode converter to facilitate optical coupling of the received lasing mode between the QD layer and the waveguide.