A waveguide grating. The waveguide grating includes a rib composed of a first material. A first portion of the waveguide has a first layer on the rib, the first layer being composed of a second material; and a second layer on the first layer, the second layer being composed of a third material, the third material having a higher index of refraction than the first material.

An implantable optical sensor (1) comprising a substrate (2) and at least one optical microstructure (3) for evanescent field sensing integrated with the substrate (2), the at least one optical microstructure (3) being positioned to form an optical interaction area (4) on a part of a surface (5) of the substrate (2), the optical assembly (1) further comprising a thin protective layer (6) covering at least the optical interaction area (4), the thin protective layer (6) being in a predetermined material with corrosion-protection characteristics and having a predetermined thickness, so as not to affect the evanescent field sensing.

An integrated waveguide polarizer comprising: a plurality of silicon layers and a plurality of silicon-nitride layers; each of the plurality of silicon layers and each of the plurality of silicon-nitride layers having a first end and an opposite second end, the first end having a wide width and the second end having a narrow width, such that each silicon layer and each silicon-nitride layer have tapered shapes; wherein the pluralities of silicon and silicon-nitride layers are overlapped, such that at least a portion of each silicon-nitride layer overlaps at least a portion of each silicon layer; and a plurality of oxide layers disposed between the pluralities of silicon-nitride and silicon layers, each oxide layer creating a separation spacing between each silicon-nitride and each silicon layers; wherein, when an optical signal is launched through the integrated waveguide polarizer, the optical signal is transitioned between each silicon-nitride layer and each silicon layer.

Provided is a photoelectric detector, comprising: a silicon layer (110), the silicon layer (110) comprising a first-doping-type doped region (111); a germanium layer (120) in contact with the silicon layer (110), the germanium layer (120) comprising a second-doping-type doped region (121); and a silicon nitride waveguide (130), the silicon nitride waveguide (130) being arranged surrounding the germanium layer (120) along the extension directions of at least three side walls of the germanium layer (120), wherein the silicon nitride waveguide (130) is used for transmitting an optical signal and coupling the optical signal to the germanium layer (120), and the germanium layer (120) is used for detecting the optical signal and converting the optical signal into an electrical signal.

Described herein are stacked photonic integrated circuit (PIC) assemblies that include multiple layers of waveguides. The waveguides are formed of substantially monocrystalline materials, which cannot be repeatedly deposited. Layers of monocrystalline material are fabricated and repeatedly transferred onto the PIC structure using a layer transfer process, which involves bonding a monocrystalline material using a non-monocrystalline bonding material. Layers of isolation materials are also deposited or layer transferred onto the PIC assembly.

A mode field adapter (MFA) is disclosed. The MFA is tapered and includes a passive core region and an active core region separated by a distance. Further, the passive core region includes first and second passive layers that are separated by another distance. The MFA is configured to receive an optical signal from a first waveguide, and alter, for transmission to a second waveguide, an optical mode of the optical signal. The optical mode is altered based on the distance between the first and second passive layers, the distance between the active and passive core regions, and the tapering of the MFA. The optical mode is altered such that an optical loss associated with the optical signal traversing from the first waveguide to the second waveguide by way of the MFA is within a tolerance limit.

A photonic integrated circuit device includes a semiconductor substrate (e.g., wafer) having a chip region therein, which is bounded on at least one side thereof by a scribe line. The chip region includes an optical transmitter, an optical receiver and a test optical waveguide. This test optical waveguide is coupled to the optical transmitter and the optical receiver and overlaps the scribe line. During a substrate dicing operation, a portion of the test optical waveguide overlapping the scribe line is removed.

Techniques disclosed herein relate to devices that each include one or more photonic integrated circuits and/or one or more electronic integrated circuits. In one embodiment, a device includes a silicon substrate, a die stack bonded (e.g., fusion-bonded) on the silicon substrate, and a printed circuit board (PCB) bonded on the silicon substrate, where the PCB is electrically coupled to the die stack. The die stack includes a photonic integrated circuit (PIC) that includes a photonic integrated circuit, and an electronic integrated circuit (EIC) die that includes an electronic integrated circuit, where the EIC die and the PIC die are bonded face-to-face (e.g., by fusion bonding or hybrid bonding) such that the photonic integrated circuit and the electronic integrated circuit face each other. In some embodiments, the device also includes a plurality of optical fibers coupled to the photonic integrated circuit.

An optical engine. In some embodiments, the optical engine includes an electronic interfacing component including: an upper surface having a plurality of conductors for forming a corresponding plurality of connections to a host board, a lower surface having a plurality of conductors for forming a corresponding plurality of connections to one or more optoelectronic elements, and a plurality of vias extending from the lower surface to the upper surface.

A LIDAR system includes a light source configured to output a source signal. The LIDAR chip is also configured to output a LIDAR output signal that exits from the LIDAR chip. The LIDAR system also includes an isolator adapter that includes an optical isolator configured to receive an adapter signal. The adapter signal includes light that is from the source signal and that has exited from the LIDAR chip before being received by the optical isolator. The isolator is configured to output light from the adapter signal in an isolator output signal. Additionally, the LIDAR output signal includes light from the isolator output signal.