In an example, a coupled system includes a first waveguide, at least one second waveguide, and an interposer. The first waveguide has a silicon (Si) core having first refractive index n1 and a tapered end. The at least one second waveguide each has a silicon nitride (SiN) core having a second refractive index n2. The interposer includes a third waveguide having a third refractive index n3 and a coupler portion, where n1>n2>n3. The tapered end of the first waveguide is adiabatically coupled to a coupler portion of one of the at least one second waveguide. A tapered end of one of the at least one second waveguide is adiabatically coupled to the coupler portion of the third waveguide of the interposer. The third waveguide of the interposer has an optical mode size that is similar to the mode size of a standard single mode optical fiber.

In an example, a photonic system includes a Si PIC with a Si substrate, a SiO.sub.2 box formed on the Si substrate, a first layer, and a second layer. The first layer is formed above the SiO.sub.2 box and includes a SiN waveguide with a coupler portion at a first end and a tapered end opposite the first end. The second layer is formed above the SiO.sub.2 box and vertically displaced above or below the first layer. The second layer includes a Si waveguide with a tapered end aligned in two orthogonal directions with the coupler portion of the SiN waveguide such that the tapered end of the Si waveguide overlaps in the two orthogonal directions and is parallel to the coupler portion of the SiN waveguide. The tapered end of the SiN waveguide is configured to be adiabatically coupled to a coupler portion of an interposer waveguide.

A light shield may be formed in photonic integrated circuit between integrated optical devices of the photonic integrated circuit. The light shield may be built by using materials already present in the photonic integrated circuit, for example the light shield may include metal walls and doped semiconductor regions. Light-emitting or light-sensitive integrated optical devices or modules of a photonic integrated circuit may be constructed with light shields integrally built in.

A method and system for coupling optical signals into silicon optoelectronic chips are disclosed and may include coupling one or more optical signals into a back surface of a CMOS photonic chip comprising photonic, electronic, and optoelectronic devices. The devices may be integrated in a front surface of the chip and one or more optical couplers may receive the optical signals in the front surface of the chip. The optical signals may be coupled into the back surface of the chip via one or more optical fibers and/or optical source assemblies. The optical signals may be coupled to the grating couplers via a light path etched in the chip, which may be refilled with silicon dioxide. The chip may be flip-chip bonded to a packaging substrate. Optical signals may be reflected back to the grating couplers via metal reflectors, which may be integrated in dielectric layers on the chip.

An optical apparatus includes an optical waveguide located on a substrate and including a guiding portion and a taper portion, and a grating pattern located on the substrate. The grating pattern includes a plurality of low refractive index portions and a plurality of high refractive index portions, which are alternately arranged in a first direction parallel to a top surface of the substrate. Each of the plurality of high refractive index portions includes a curved inner sidewall and a curved outer sidewall having curvatures defined by circular paths. The inner sidewall and the outer sidewall of at least one of the plurality of high refractive index portions have a first focus position. The inner sidewall or the outer sidewall of at least one of the plurality of high refractive index portions or a sidewall of the taper portion has a second focus position different from the first focus position.

A light shield may be formed in photonic integrated circuit between integrated optical devices of the photonic integrated circuit. The light shield may be built by using materials already present in the photonic integrated circuit, for example the light shield may include metal walls and doped semiconductor regions. Light-emitting or light-sensitive integrated optical devices or modules of a photonic integrated circuit may be constructed with light shields integrally built in.

An electronic power cell memory back-up battery is disclosed. The electronic power cell memory back-up battery utilizes stored light photons to produce usable energy, and can be used to replace batteries or other power sources in electronic devices. The electronic power cell memory back-up battery disclosed includes a light source and a photovoltaic device in optical communication with the light source. The photovoltaic device creates electrical power in response to receiving light from the light source. A portion of the electrical power generated by the photovoltaic device is used to power the light source. In some embodiments power input contacts are included for use in providing initial start-up power to the light source. In some embodiments the light source comprises a light-emitting device and a photoluminescent material optically coupled to the light-emitting device, where the photoluminescent material emits light in response to receiving light from the light-emitting device.

A method and system for coupling optical signals into silicon optoelectronic chips are disclosed and may include coupling one or more optical signals into a back surface of a CMOS photonic chip comprising photonic, electronic, and optoelectronic devices. The devices may be integrated in a front surface of the chip and one or more optical couplers may receive the optical signals in the front surface of the chip. The optical signals may be coupled into the back surface of the chip via one or more optical fibers and/or optical source assemblies. The optical signals may be coupled to the grating couplers via a light path etched in the chip, which may be refilled with silicon dioxide. The chip may be flip-chip bonded to a packaging substrate. Optical signals may be reflected back to the grating couplers via metal reflectors, which may be integrated in dielectric layers on the chip.

A light shield may be formed in photonic integrated circuit between integrated optical devices of the photonic integrated circuit. The light shield may be built by using materials already present in the photonic integrated circuit, for example the light shield may include metal walls and doped semiconductor regions. Light-emitting or light-sensitive integrated optical devices or modules of a photonic integrated circuit may be constructed with light shields integrally built in.

A non-reciprocal coupler isolator is provided including a first waveguide. The first waveguide includes a magnetic cladding cover layer magnetized transversely to a propagation direction of the first waveguide. A second waveguide is positioned adjacent to the first waveguide and separated by a gap. The second waveguide includes a non-magnetic cladding cover layer with a refractive index that matches a refractive index of the magnetic cladding cover layer of the first waveguide.