Abstract: A fiber coupler (135) for coupling a plurality of cores (160) of a multi-core optical fiber (105) to an integrated photonic device comprises a grating array comprising a plurality of polarization splitting gratings (180) arranged in a manner that corresponds to the plurality of cores (160) in the multi-core optical fiber (105). The fiber coupler (135) also comprises first and second mode converters (235, 240) extending from first and second sides of each of the plurality of polarization splitting gratings (180) to receive first and second polarization modes of the optical signal scattered by the polarization splitting grating (180). A plurality of waveguides (145-a, 145-b) extends from ends of each of the mode converters (235, 240) to guide a single polarization mode of one of the optical signals.

Abstract: Methods, systems, and devices are disclosed for using optical modes in optical waveguides to carry different optical communication signals. In one aspect, an optical device for optical MDM in optical communications includes an optical waveguide configured to support multiple optical waveguide modes and to carry light of different optical communication channels in different optical waveguide modes, respectively, of the multiple optical waveguide modes. The optical device includes an optical resonator configured to be capable of carrying an optical communication channel in one optical resonator mode and optically coupled to the optical waveguide to selectively couple the optical communication channel in the optical resonator into the optical waveguide to add a channel into the optical waveguide via optical mode division multiplexing. In another aspect, an optical mode division demultiplexing can be performed by coupling an optical waveguide and an optical resonator.

Abstract: Methods, systems, and devices are disclosed for using optical modes in optical waveguides to carry different optical communication signals. In one aspect, an optical device for optical MDM in optical communications includes an optical waveguide configured to support multiple optical waveguide modes and to carry light of different optical communication channels in different optical waveguide modes, respectively, of the multiple optical waveguide modes. The optical device includes an optical resonator configured to be capable of carrying an optical communication channel in one optical resonator mode and optically coupled to the optical waveguide to selectively couple the optical communication channel in the optical resonator into the optical waveguide to add a channel into the optical waveguide via optical mode division multiplexing. In another aspect, an optical mode division demultiplexing can be performed by coupling an optical waveguide and an optical resonator.

Abstract: The resolution of conventional imaging devices is restricted by the diffraction limit. ‘Perfect’ imaging devices which can achieve a resolution beyond the diffraction limit have been considered impossible to implement. However, the present disclosure provides an imaging device which can achieve improved resolution beyond the diffraction limit and which can be implemented in practice. Said imaging device comprises: a. a lens having a refractive index that varies according to a predetermined refractive index profile; b. a source; c. an outlet for decoupling waves from the device; and d. a reflector provided around the lens, the source and the outlet, wherein the reflector and the refractive index profile of the lens are together arranged to direct waves transmitted in any of a plurality of directions from the source to the outlet.

Abstract: Methods, systems, and devices are disclosed for using optical modes in optical waveguides to carry different optical communication signals. In one aspect, an optical device for optical MDM in optical communications includes an optical waveguide configured to support multiple optical waveguide modes and to carry light of different optical communication channels in different optical waveguide modes, respectively, of the multiple optical waveguide modes. The optical device includes an optical resonator configured to be capable of carrying an optical communication channel in one optical resonator mode and optically coupled to the optical waveguide to selectively couple the optical communication channel in the optical resonator into the optical waveguide to add a channel into the optical waveguide via optical mode division multiplexing. In another aspect, an optical mode division demultiplexing can be performed by coupling an optical waveguide and an optical resonator.

Abstract: Techniques and devices are disclosed to provide controlled inter-mode cross-talk in multimode optical waveguides. The structure of a bent multimode optical waveguide can be designed or configured in a way that either substantially minimizes inter-mode cross talk or achieves a desired inter-mode cross-talk. Specific examples based on the disclosed waveguide designs are provided for semiconductor integrated waveguide devices.

Abstract: The resolution of conventional imaging devices is restricted by the diffraction limit ‘Perfect’ imaging devices which can achieve a resolution beyond the diffraction limit have been considered impossible to implement. However, the present disclosure provides an imaging device which can achieve improved resolution beyond the diffraction limit and which can be implemented in practice. Said imaging device comprises: a. a lens having a refractive index that varies according to a predetermined refractive index profile; b. a source; c. an outlet for decoupling waves from the device; and d. a reflector provided around the lens, the source and the outlet, wherein the reflector and the refractive index profile of the lens are together arranged to direct waves transmitted in any of a plurality of directions from the source to the outlet.

Abstract: Techniques and devices are disclosed to provide controlled inter-mode cross-talk in multimode optical waveguides. The structure of a bent multimode optical waveguide can be designed or configured in a way that either substantially minimizes inter-mode cross talk or achieves a desired inter-mode cross-talk. Specific examples based on the disclosed waveguide designs are provided for semiconductor integrated waveguide devices.

Abstract: The resolution of conventional imaging devices is restricted by the diffraction limit ‘Perfect’ imaging devices which can achieve a resolution beyond the diffraction limit have been considered impossible to implement. However, the present disclosure provides an imaging device which can achieve improved resolution beyond the diffraction limit and which can be implemented in practice. Said imaging device comprises: a. a lens having a refractive index that varies according to a predetermined refractive index profile; b. a source; c. an outlet for decoupling waves from the device; and d. a reflector provided around the lens, the source and the outlet, wherein the reflector and the refractive index profile of the lens are together arranged to direct waves transmitted in any of a plurality of directions from the source to the outlet.

Abstract: The resolution of conventional imaging devices is restricted by the diffraction limit. ‘Perfect’ imaging devices which can achieve a resolution beyond the diffraction limit have been considered impossible to implement. However, the present disclosure provides an imaging device which can achieve improved resolution beyond the diffraction limit and which can be implemented in practice. Said imaging device comprises: a. a lens having a refractive index that varies according to a predetermined refractive index profile; b. a source; c. an outlet for decoupling waves from the device; and d. a reflector provided around the lens, the source and the outlet, wherein the reflector and the refractive index profile of the lens are together arranged to direct waves transmitted in any of a plurality of directions from the source to the outlet.