A fast optical switch can be fabricated/constructed, when vanadium dioxide (VO.sub.2) ultra thin-film or a cluster of vanadium dioxide particles (less than 0.5 microns in diameter) embedded in an ultra thin-film of a polymeric material or in a mesh of metal nanowires is activated by either an electrical pulse (a voltage pulse or a current pulse) or a light pulse just to induce rapid insulator-to-metal phase transition (IMT) in vanadium dioxide ultra thin-film or vanadium dioxide particles embedded in an ultra thin-film of a polymeric material or in a mesh of metal nanowires. The applications of such a fast optical switch for an on-Demand optical add-drop subsystem, integrating with or without a wavelength converter are also described.

Systems and methods for activation in an optical circuit in accordance with embodiments of the invention are illustrated. One embodiment includes an optical activation circuit, wherein the circuit comprises a directional coupler, an optical-to-electrical conversion circuit, a time delay element, a nonlinear signal conditioner, and a phase shifter. The directional coupler receives an optical input and provides a first portion to the optical-to-electrical conversion circuit and a second portion to the time delay element, the time delay element provides a delayed signal to the phase shifter, and the optical-to-electrical conversion circuit converts an optical signal from the directional coupler to an electrical signal used to activate the phase shifter to shift the phase of the delayed signal.

Systems and methods for activation in an optical circuit in accordance with embodiments of the invention are illustrated. One embodiment includes an optical activation circuit, wherein the circuit comprises a directional coupler, an optical-to-electrical conversion circuit, a time delay element, a nonlinear signal conditioner, and a phase shifter. The directional coupler receives an optical input and provides a first portion to the optical-to-electrical conversion circuit and a second portion to the time delay element, the time delay element provides a delayed signal to the phase shifter, and the optical-to-electrical conversion circuit converts an optical signal from the directional coupler to an electrical signal used to activate the phase shifter to shift the phase of the delayed signal.

In the examples provided herein, an optical logic gate includes multiple couplers, where no more than two types of couplers are used in the optical logic gate, and further wherein the two types of couplers consist of: a 3-dB coupler and a weak coupler with a given transmission-to-reflection ratio. The optical logic gate also includes a first resonator, wherein the first resonator comprises a photonic crystal resonator or a nonlinear ring resonator, wherein in operation, the first resonator has a dedicated continuous wave input to bias a complex amplitude of a total field input to the first resonator such that the total field input is either above or below a nonlinear switching threshold of the first resonator, where the optical logic gate is an integrated photonic circuit.

In the examples provided herein, an optical logic gate includes multiple couplers, where no more than two types of couplers are used in the optical logic gate, and further wherein the two types of couplers consist of: a 3-dB coupler and a weak coupler with a given transmission-to-reflection ratio. The optical logic gate also includes a first resonator, wherein the first resonator comprises a photonic crystal resonator or a nonlinear ring resonator, wherein in operation, the first resonator has a dedicated continuous wave input to bias a complex amplitude of a total field input to the first resonator such that the total field input is either above or below a nonlinear switching threshold of the first resonator, where the optical logic gate is an integrated photonic circuit.

In the examples provided herein, an optical logic gate includes multiple couplers, where no more than two types of couplers are used in the optical logic gate, and further wherein the two types of couplers consist of: a 3-dB coupler and a weak coupler with a given transmission-to-reflection ratio. The optical logic gate also includes a first resonator, wherein the first resonator comprises a photonic crystal resonator or a nonlinear ring resonator, wherein in operation, the first resonator has a dedicated continuous wave input to bias a complex amplitude of a total field input to the first resonator such that the total field input is either above or below a nonlinear switching threshold of the first resonator, where the optical logic gate is an integrated photonic circuit.

A switch activated by a single control photon for routing a single target photon from either of two switch inputs to either of two switch outputs. The device is based on a single quantum emitter, such as an atom, coupled to a fiber-coupled, chip-based optical micro-resonator. A single reflected control photon toggles the switch from high reflection to high transmission mode, with no additional control fields required. The control and target photons are both in-fiber and practically identical, for compatibility with scalable architectures for quantum information processing.

An optical modulator connected to a first optical fiber and a second optical fiber arranged in parallel includes an optical-path changing unit that redirects light emerging from a tip of the first optical fiber toward a tip of the second optical fiber and an optical modulation chip that modulates the light redirected by the optical-path changing unit and outputs a light beam obtained by modulating the light to a tip of the second optical fiber.

A fast optical switch can be fabricated/constructed, when a vanadium dioxide (VO.sub.2) and a two-dimensional (2-D) material is activated by either an electrical pulse (a voltage pulse or a current pulse) or a light pulse just to induce an insulator-to-metal phase transition (IMT) in vanadium dioxide. The applications of such a fast optical switch for an on-demand optical add-drop subsystem, integrating with (a) a light slowing/light stopping component (based on metamaterials and/or nanoplasmonic structures) and (b) with or without a wavelength converter are also described.

A fast optical switch can be fabricated/constructed, when a vanadium dioxide (VO.sub.2) and a two-dimensional (2-D) material is activated by either an electrical pulse (a voltage pulse or a current pulse) or a light pulse just to induce an insulator-to-metal phase transition (IMT) in vanadium dioxide. The applications of such a fast optical switch for an on-demand optical add-drop subsystem, integrating with (a) a light slowing/light stopping component (based on metamaterials and/or nanoplasmonic structures) and (b) with or without a wavelength converter are also described.