A converter includes a combiner configured to polarization-combine a first pump light and a second pump light, a nonlinear medium configured to wavelength-convert first signal light into second signal light to output the second signal light after wavelength conversion from a second port, and to wavelength-convert the second signal light into first signal light to output the first signal light after wavelength conversion from the first port, a first circulator configured to input the first signal light from the first port into the nonlinear medium, and output the first signal light after wavelength conversion in the nonlinear medium from the first port, and a second circulator configured to input the second signal light from the second port into the nonlinear medium, and output the second signal light after wavelength conversion in the nonlinear medium from the second port.

The receiver including a package, first and second optical fibers, a capillary, and an array lens is disclosed. The first fiber has a first edge coupling to a MMI device by propagating a signal beam. The second fiber has a second edge coupling to the MMI device by propagating a local beam. The array lens has first and second lenses. The first lens converts the signal beam into a collimating beam, and the second lens converts the local beam into a collimating beam. The capillary has an edge opposite to the array lens, and the edge has a first region including the first edge and a second region including the second edge. The first edge is slanted to a first axis, and the second edge is slanted to a second axis, and a direction of the first edge and a direction of the second edge are different each other.

A wavelength conversion device that converts input signal light having a first frequency into output signal light having a second frequency, includes: a control-light generator that outputs first continuous oscillation light and second continuous oscillation light; and a nonlinear optical medium that cross-phase modulates the input signal light with the first continuous oscillation light and the second continuous oscillation light and generates the output signal light, wherein the control-light generator outputs the first continuous oscillation light and the second continuous oscillation light to have polarized waves in directions orthogonal to each other and have a frequency interval equal to a difference between the first frequency and the second frequency and controls, based on intensity of the output signal light, timings of modulation of phases of the first continuous oscillation light and the second continuous oscillation light to be aligned with each other.

Devices, systems and methods for encoding information using optical components are described. An example photonic filtered sampler includes a spectral shaper configured to receive an optical pulse train, a dispersive element positioned to receive an output of the spectral shaper and to expand spectral contents thereof in time, and a modulator configured to receive an output of the dispersive element and a radio frequency (RF) signal, and to produce a modulated output optical signal in accordance with the RF signal. In this configuration, one or more characteristics of the modulated output optical signal is determined based on a spectral shape provided by the spectral shaper and dispersive properties of the dispersive element.

A fast optical (with or without a photonic crystal) switch is fabricated/constructed, utilizing a phase transition material/Mott insulator, activated by either an electrical pulse (a voltage pulse or a current pulse) and/or a light pulse and/or pulses in terahertz (THz) frequency of a suitable field strength and/or hot electrons. 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 light source comprising an excitation light source for providing excitation light, and an optical wavelength conversion member disposed at a distance from the excitation light source. The optical wavelength conversion member comprises an optical wavelength conversion material for converting the excitation light into stimulated light. The light source also comprises an optical-guiding member that allows the excitation light to be incident on the optical wavelength conversion material, and an optical-collecting member for collecting converted light originating from the optical wavelength conversion material. To separate the paths of the converted light and the excitation light, the etendue of the optical-guiding member is less than or equal to of the etendue of the optical-collecting member. This allows the optical-guiding member to draw in the excitation light while preventing the excessive escape of the converted light through the optical-guiding member.

A wavelength conversion device that converts input signal light having a first frequency into output signal light having a second frequency, includes: a control-light generator that outputs first continuous oscillation light and second continuous oscillation light; and a nonlinear optical medium that cross-phase modulates the input signal light with the first continuous oscillation light and the second continuous oscillation light and generates the output signal light, wherein the control-light generator outputs the first continuous oscillation light and the second continuous oscillation light to have polarized waves in directions orthogonal to each other and have a frequency interval equal to a difference between the first frequency and the second frequency and controls, based on intensity of the output signal light, timings of modulation of phases of the first continuous oscillation light and the second continuous oscillation light to be aligned with each other.

Devices, systems and methods for encoding information using optical components are described. An example photonic filtered sampler includes a spectral shaper configured to receive an optical pulse train, a dispersive element positioned to receive an output of the spectral shaper and to expand spectral contents thereof in time, and a modulator configured to receive an output of the dispersive element and a radio frequency (RF) signal, and to produce a modulated output optical signal in accordance with the RF signal. In this configuration, one or more characteristics of the modulated output optical signal is determined based on a spectral shape provided by the spectral shaper and dispersive properties of the dispersive element.

A wavelength conversion device that converts input signal light having a first frequency into output signal light having a second frequency, includes: a control-light generator that outputs first continuous oscillation light and second continuous oscillation light; and a nonlinear optical medium that cross-phase modulates the input signal light with the first continuous oscillation light and the second continuous oscillation light and generates the output signal light, wherein the control-light generator outputs the first continuous oscillation light and the second continuous oscillation light to have polarized waves in directions orthogonal to each other and have a frequency interval equal to a difference between the first frequency and the second frequency and controls, based on intensity of the output signal light, timings of modulation of phases of the first continuous oscillation light and the second continuous oscillation light to be aligned with each other.

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.