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.

An optical switch has four optical ports; a first optical waveguide coupled between a first of said ports and a second of the ports; a first switch element provided between the first waveguide and a second optical waveguide that is coupled to a third of the ports; a second switch element provided between the first waveguide and a third optical waveguide that is coupled to a fourth of the ports. Each switch element has a micro-ring resonator having an active state in which it is coupled to the first waveguide and to a respective one of the second and third waveguides for optical signals at a preselected wavelength, and an inactive state in which no coupling occurs. Each switch element has a control element arranged to receive a respective control signal configured to cause it to switch the micro-ring resonator between said states.

Provided is an optical modulator including: a relay substrate; a first transmission line that is provided on a flat surface of the relay substrate, and transmits, along the flat surface of the relay substrate, an electrical signal that has been input from an outer side; a second transmission line that is provided in the relay substrate, and transmits the electrical signal in a direction that is not included in the flat surface; a modulation unit that modulates an optical signal by using the electrical signal that is transmitted by the first transmission line and the second transmission line; and a shield that shields a radiation component of the electrical signal that is radiated from a contact of the first transmission line and the second transmission line.

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 fiber optic cable assembly includes an elongate housing, a signal fiber placed inside the housing and extending longitudinally, and a plurality of sensing fibers placed inside the housing and extending longitudinally. The plurality of sensing fibers is placed around the signal fiber. Each of the plurality of sensing fibers carries a respective laser signal of a distinct frequency. The signal fiber carries one or more evanescent coupling signals responsive to the laser signals in the plurality of sensing fibers.

A fiber optic cable assembly includes an elongate housing, a signal fiber placed inside the housing and extending longitudinally, and a plurality of sensing fibers placed inside the housing and extending longitudinally. The plurality of sensing fibers is placed around the signal fiber. Each of the plurality of sensing fibers carries a respective laser signal of a distinct frequency. The signal fiber carries one or more evanescent coupling signals responsive to the laser signals in the plurality of sensing fibers.

An optical device includes at least three optical ports. An optical arrangement arranges an optical beam received from any of the optical ports into a first polarization state. A dispersion element spatially separates the optical beam into a plurality of wavelength components. An optical power element converges each wavelength component in at least one direction. A programmable optical phase modulator steers the wavelength components through the optical arrangement, the dispersion element and the focusing element to a selected optical output. The programmable optical phase modulator includes an active area that performs the steering and a non-active area surrounding the active area. A polarizing arrangement located in an optical path between at least one of the optical ports and at least a portion of the non-active area of the programmable optical phase modulator is configured to arrange optical energy into a second polarization state orthogonal to the first polarization state.

A fiber optic cable assembly includes an elongate housing, a signal fiber placed inside the housing and extending longitudinally, and a plurality of sensing fibers placed inside the housing and extending longitudinally. The plurality of sensing fibers is placed around the signal fiber. Each of the plurality of sensing fibers carries a respective laser signal of a distinct frequency. The signal fiber carries one or more evanescent coupling signals responsive to the laser signals in the plurality of sensing fibers.

A fiber optic cable assembly includes an elongate housing, a signal fiber placed inside the housing and extending longitudinally, and a plurality of sensing fibers placed inside the housing and extending longitudinally. The plurality of sensing fibers is placed around the signal fiber. Each of the plurality of sensing fibers carries a respective laser signal of a distinct frequency. The signal fiber carries one or more evanescent coupling signals responsive to the laser signals in the plurality of sensing fibers.

A fiber optic cable assembly includes an elongate housing, a signal fiber placed inside the housing and extending longitudinally, and a plurality of sensing fibers placed inside the housing and extending longitudinally. The plurality of sensing fibers is placed around the signal fiber. Each of the plurality of sensing fibers carries a respective laser signal of a distinct frequency. The signal fiber carries one or more evanescent coupling signals responsive to the laser signals in the plurality of sensing fibers.