Systems and embodiments for an integrated photonics mode splitter and converter are provided herein. In certain embodiments, a system includes a substrate having a first index of refraction. Additionally, the system includes a waveguide layer on the substrate, wherein the waveguide has a second index of refraction different from the first index of refraction. Also, the waveguide layer includes one or more mode splitters that receive at least one of a first photon in a first mode and a second photon in a second mode through an input port and provide one of the first photon through a first output port and the second photon through a second output port. The waveguide layer also includes a mode converter coupled to the second output of a mode splitter, wherein the mode converter receives the second photon through a port and outputs the second photon in the first mode through the port.

A lightguide optical element (LOE) configured for polarization scrambling is provided. The LOE includes a transparent substrate having a first refractive index, the substrate having a pair of parallel external surfaces configured to propagate light within the LOE through total internal reflection (TIR), and a plurality of mutually parallel partially reflective internal surfaces, those being non-parallel to the pair of parallel external surfaces and configured to couple out said light to a viewer. The LOE further includes a first coating on at least one external surface of the substrate, the first coating being of a coating material having a second refractive index higher than the first refractive index; The LOE further includes an antireflective (AR) coating on at least one external surface of the substrate over the first coating.

A chip-scale coherent lidar system includes a master oscillator integrated on a chip to simultaneously provide a signal for transmission and a local oscillator (LO) signal. The system also includes a beam steering device to direct an output signal obtained from the signal for transmission out of the system, and a combiner on the chip to combine the LO signal and a return signal resulting from a reflection of the output signal by a target. One or more photodetectors obtain a result of interference between the LO signal and the return signal to determine information about the target.

In accordance with an example embodiment of the present invention, there is provided an apparatus (160) comprising two inputs configured to receive two optical signals from two fibres (155, 157) from two respective optical transmitters, a beam splitter configured to convert the optical signals into dual rail form, the apparatus being configured to cause the optical signals to interfere with each other, a plurality of single photon detectors configured to measure the dual rail form optical signals, and at least one processing core configured to obtain compensation adjustment information concerning the two fibres and to inform the optical transmitters of the compensation adjustment information.

A wavelength converter includes a polarization beam splitter configured to separate input light into a first polarization and a second polarization that are orthogonal to each other a non-linear optical medium configured to include a first incident end on which the first polarization separated by the polarization beam splitter is incident and a second incident end on which the second polarization separated by the polarization beam splitter is incident at a position different from a position of the first incident end, an optical multiplexer configured to multiplex the first polarization that has passed through the non-linear optical medium and the second polarization that has passed through the non-linear optical medium, and an optical element arranged between the non-linear optical medium and the optical multiplexer, and configured to correct a polarization axis of at least one of the first polarization and the second polarization incident on the optical multiplexer.

In accordance with an example embodiment of the present invention, there is provided an apparatus (160) comprising two inputs configured to receive two optical signals from two fibres (155, 157) from two respective optical transmitters, a beam splitter configured to convert the optical signals into dual rail form, the apparatus being configured to cause the optical signals to interfere with each other, a plurality of single photon detectors configured to measure the dual rail form optical signals, and at least one processing core configured to obtain compensation adjustment information concerning the two fibres and to inform the optical transmitters of the compensation adjustment information.

An optical device is provided. The optical device includes a fiber array and an optical assembly. The fiber array includes a common channel and a plurality of divided channels arranged in parallel in a first direction and extending along a second direction, and the fiber array has a first surface from a top view perspective. The optical assembly is coupled to the first surface of the fiber array. The first surface and the common channel of the fiber array form an angle less than 90 degrees from the top view perspective.

A polarization rotator structure includes: a first core structure formed at a first layer, extending from the first end to a second end, and a second core structure formed at a second layer that is at a different depth than the first layer and formed in proximity to the first core structure. The first core structure and the second core structure provide mode hybridization between at least two orthogonally polarized waveguide modes of the PRS. An optical splitter structure is optically coupled at a first end to the second end of the PRS, and optically coupled at a second end to at least two optical waveguides, and includes: a first core structure that is contiguous with at least one of the first or second core structures of the PRS, and a second core structure that is separate from both of the first and second core structures of the PRS.

An electro-optic receiver includes a polarization splitter and rotator (PSR) that directs incoming light having a first polarization through a first end of an optical waveguide, and that rotates incoming light from a second polarization to the first polarization to create polarization-rotated light that is directed to a second end of the optical waveguide. The incoming light of the first polarization and the polarization-rotated light travel through the optical waveguide in opposite directions. A plurality of ring resonators is optically coupled the optical waveguide. Each ring resonator is configured to operate at a respective resonant wavelength, such that the incoming light of the first polarization having the respective resonant wavelength optically couples into said ring resonator in a first propagation direction, and such that the polarization-rotated light having the respective resonant wavelength optically couples into said ring resonator in a second propagation direction opposite the first propagation direction.

Silicon photonics provides an attractive platform for optoelectronic integrated circuits (OEICs) exploiting hybrid or monolithic integration with or without concurrent integration of microelectromechanical systems (MEMS) and/or CMOS electronic. Such OEICs offering optical component solutions across multiple applications from optical sensors through to optical networks operating upon one or more wavelengths. Accordingly, various silicon photonic building blocks are required in order to provide a toolkit for a circuit designer to exploit OEICs where these building blocks must address specific aspects of OEICs such as polarisation dependency of the optical waveguides. Accordingly, the inventors have established designs for: polarisation rotators with MEMS based tuning to allow the dual polarisations from a polarisation splitter to be managed by an OEIC operating upon a single polarisation; analog or digital phase shifts with MEMS actuation for switches, attenuators etc.; and passband filters with MEMS tuning.