Abstract: A visibly transparent planar structure using a CPA scheme to boost the absorption of a multi-layer thin-film configuration, requiring no surface patterning, to overcome the intrinsic absorption limitation of the absorbing material. This is achieved in a multi-layer absorbing Fabry-Perot (FP) cavity, namely a thin-film amorphous silicon solar cell. Omni-resonance is achieved across a bandwidth of 80 nm in the near-infrared (NIR), thus increasing the effective absorption of the material, without modifying the material itself, enhancing it beyond its intrinsic absorption over a considerable spectral range. The apparatus achieved an increased external quantum efficiency (EQE) of 90% of the photocurrent generated in the 80 nm NIR region from 660 to 740 nm as compared to a bare solar cell. over the spectral range of interest.

Abstract: A visibly transparent planar structure using a CPA scheme to boost the absorption of a multi-layer thin-film configuration, requiring no surface patterning, to overcome the intrinsic absorption limitation of the absorbing material. This is achieved in a multi-layer absorbing Fabry-Perot (FP) cavity, namely a thin-film amorphous silicon solar cell. Omni-resonance is achieved across a bandwidth of 80 nm in the near-infrared (NIR), thus increasing the effective absorption of the material, without modifying the material itself, enhancing it beyond its intrinsic absorption over a considerable spectral range. The apparatus achieved an increased external quantum efficiency (EQE) of 90% of the photocurrent generated in the 80 nm NIR region from 660 to 740 nm as compared to a bare solar cell. over the spectral range of interest.

Abstract: The present disclosure is directed to systems and methods for omniresonant broadband coherent perfect absorption of incoherent light over large bandwidths. The apparatus and methods that enable 100% effective optical absorption in a structure, irrespective of the material from which it is constructed, over a large, continuous bandwidth (omniresonance) in ultrathin devices. Specifically, we demonstrate achromatic optical absorption (omniresonance) in a planar Fabry-Pérot micro-cavity via angularly multiplexed phase-matching. By assigning each wavelength to an appropriate angle of incidence, the micro-cavity is rendered absorbing with continuous spectral range. For example, the linewidth of a single-order 0.7 nm wide resonance is de-slanted in spectral-angular space to become a 70 nm wide achromatic resonance spanning multiple cavity free spectral ranges. The embodied invention can have important applications in, e.g.

Abstract: A fiber is provided that has been thermally drawn from a fiber preform, having a longitudinal-axis length and including at least one core that has a longitudinal core axis parallel to the longitudinal axis and internally disposed to at least one outer fiber cladding material layer along the fiber length. The fiber is fed through a localized heating site having a heating site temperature, T, that is above a melting temperature of the fiber core, with a feed speed, ?f, that melts a portion of the fiber core at the heating site, causing molten droplets to pinch off of fiber core material, one droplet at a time, with a time period of molten droplet formation set by the fiber feed speed, ?f. The fiber is fed through the localized heating site to move the molten droplets out of the heating site and solidify the molten droplets into solid in-fiber particles.

Abstract: The present disclosure is directed to systems and methods for omniresonant broadband coherent perfect absorption of incoherent light over large bandwidths. The apparatus and methods that enable 100% effective optical absorption in a structure, irrespective of the material from which it is constructed, over a large, continuous bandwidth (omniresonance) in ultrathin devices. Specifically, we demonstrate achromatic optical absorption (omniresonance) in a planar Fabry-Pérot micro-cavity via angularly multiplexed phase-matching. By assigning each wavelength to an appropriate angle of incidence, the micro-cavity is rendered absorbing with continuous spectral range. For example, the linewidth of a single-order 0.7 nm wide resonance is de-slanted in spectral-angular space to become a 70 nm wide achromatic resonance spanning multiple cavity free spectral ranges. The embodied invention can have important applications in, e.g.

Abstract: In one embodiment, a chalcogenide glass optical fiber is produced by forming a billet including a chalcogenide glass mass and a polymer mass in a stacked configuration, heating the billet to a temperature below the melting point of the chalcogenide glass, extruding the billet in the ambient environment to form a preform rod having a chalcogenide glass core and a polymer jacket, and drawing the preform rod.

Abstract: An underwater fiber optic cable includes an optical fiber, and a jacket surrounding the optical fiber. The jacket includes a polymer having a first density, and particles distributed throughout the polymer having a second density greater than the first density. The particles have a predetermined volume fraction to thereby provide the underwater cable with a predetermined buoyancy when underwater.

Abstract: A thin film photonic structure that enables segregation of the effective absorption of the thin film and its intrinsic absorption while substantially eliminating bandwidth restrictions. In the form of an optical resonator, the structure includes two, multi-layer, aperiodic dielectric mirrors and a lossy, dielectric thin film and characterized by an intrinsic optical absorption over at least a one octave bandwidth. The two, multi-layer, aperiodic dielectric mirrors are characterized by a reflectivity amplitude that increases in-step with increasing wavelength over the at least one octave bandwidth. Upon a single incoherent beam of optical radiation having a spectrum over the at least one octave bandwidth incident on one side of the resonator structure, the lossy, dielectric thin film is characterized by an effective optical absorption over the at least one octave bandwidth that is greater than the intrinsic optical absorption over the at least one octave bandwidth.

Abstract: A thin film photonic structure that enables segregation of the effective absorption of the thin film and its intrinsic absorption while substantially eliminating bandwidth restrictions. In the form of an optical resonator, the structure includes two, multi-layer, aperiodic dielectric mirrors and a lossy, dielectric thin film and characterized by an intrinsic optical absorption over at least a one octave bandwidth. The two, multi-layer, aperiodic dielectric mirrors are characterized by a reflectivity amplitude that increases in-step with increasing wavelength over the at least one octave bandwidth. Upon a single incoherent beam of optical radiation having a spectrum over the at least one octave bandwidth incident on one side of the resonator structure, the lossy, dielectric thin film is characterized by an effective optical absorption over the at least one octave bandwidth that is greater than the intrinsic optical absorption over the at least one octave bandwidth.

Abstract: A fiber is provided, including a cladding material that is disposed along a longitudinal-axis fiber length. A plurality of spherical particles are disposed as a sequence along a longitudinal line parallel to the longitudinal fiber axis in at least a portion of the fiber length, and include a spherical particle material that is interior to the fiber cladding material and different than the fiber cladding material. To produce particles, a drawn fiber, having a longitudinal-axis fiber length and including at least one fiber core that has a longitudinal core axis parallel to the longitudinal fiber axis and that is internally disposed to at least one outer fiber cladding layer along the fiber length, is heated for a time that is sufficient to cause a fiber core to break-up into droplets sequentially disposed along the fiber core axis. Fiber cooling solidifies droplets into spherical particles interior to fiber cladding.

Abstract: There is provided a fiber including a cladding material that is disposed along a longitudinal-axis fiber length. A plurality of spherical particles are provided, separated from one another and disposed in a longitudinal line parallel to the longitudinal fiber axis. The particles are in a sequence with controlled periodic spacing between particles along at least a portion of the fiber length. Each spherical particle has a spherical particle material that is embedded within and elementally different than the fiber cladding material.

Abstract: In one embodiment, a chalcogenide glass optical fiber is produced by forming a billet including a chalcogenide glass mass and a polymer mass in a stacked configuration, heating the billet to a temperature below the melting point of the chalcogenide glass, extruding the billet in the ambient environment to form a preform rod having a chalcogenide glass core and a polymer jacket, and drawing the preform rod.

Abstract: In one embodiment, a chalcogenide glass optical fiber is produced by forming a billet including a chalcogenide glass mass and a polymer mass in a stacked configuration, heating the billet to a temperature below the melting point of the chalcogenide glass, extruding the billet in the ambient environment to form a preform rod having a chalcogenide glass core and a polymer jacket, and drawing the preform rod.

Abstract: In a fiber there is provided a fiber matrix material having a fiber length. A circumferential array of in-fiber filaments extend the fiber length. Each filament in the array is separated from other filaments in the array by the fiber matrix material. The filaments in the array are regularly spaced around a circumference at a radius in a cross section of the fiber.

Abstract: A fiber is provided, including a cladding material that is disposed along a longitudinal-axis fiber length. A plurality of spherical particles are disposed as a sequence along a longitudinal line parallel to the longitudinal fiber axis in at least a portion of the fiber length. Each spherical particle is of a spherical particle material that is interior to and different than the fiber cladding material. The spacing between adjacent spherical particles in the sequence of particles is greater than the spherical particle diameter. Each spherical particle can be provided as a core-shell particle that includes a spherical core that is surrounded by at least one spherical shell. Each spherical particle can be provided with a plurality of azimuthal sections of at least two distinct materials.

Abstract: In a fiber there is provided a fiber matrix material having a fiber length; and an array of isolated in-fiber filaments that extend the fiber length. The in-fiber filaments are disposed at a radius in a cross section of the fiber that is a location of a continuous filament material layer in a drawing preform of the fiber. As a result, there is provided a fiber matrix material having a fiber length; and a plurality of isolated fiber elements that are disposed in the fiber matrix, extending the fiber length, where the plurality is of a number greater than a number of isolated domains in a drawing preform of the fiber.

Abstract: In one embodiment, a chalcogenide glass optical fiber is produced by forming a billet including a chalcogenide glass mass and a polymer mass in a stacked configuration, heating the billet to a temperature below the melting point of the chalcogenide glass, extruding the billet in the ambient environment to form a preform rod having a chalcogenide glass core and a polymer jacket, and drawing the preform rod.

Abstract: A fiber is provided that has been thermally drawn from a fiber preform, having a longitudinal-axis length and including at least one core that has a longitudinal core axis parallel to the longitudinal axis and internally disposed to at least one outer fiber cladding material layer along the fiber length. The fiber is fed through a localized heating site having a heating site temperature, T, that is above a melting temperature of the fiber core, with a feed speed, ?f, that melts a portion of the fiber core at the heating site, causing molten droplets to pinch off of fiber core material, one droplet at a time, with a time period of molten droplet formation set by the fiber feed speed, ?f. The fiber is fed through the localized heating site to move the molten droplets out of the heating site and solidify the molten droplets into solid in-fiber particles.

Abstract: There is provided a thermal sensing fiber grid, including a plurality of rows and columns of thermal sensing fibers, each of which includes a semiconducting element that has a fiber length and that is characterized by a bandgap energy corresponding to a selected operational temperature range of the fiber in which there can be produced a change in thermally-excited electronic charge carrier population in the semiconducting element in response to a temperature change in the selected temperature range. There is included at least one pair of conducting electrodes in contact with the semiconducting element along the fiber length, and an insulator along the fiber length. An electronic circuit is provided for and connected to each thermal sensing fiber for producing an indication of thermal sensing fiber grid coordinates of a change in ambient temperature.

Abstract: In a fiber there is provided a fiber matrix material having a fiber length; and an array of isolated in-fiber filaments that extend the fiber length. The in-fiber filaments are disposed at a radius in a cross section of the fiber that is a location of a continuous filament material layer in a drawing preform of the fiber. As a result, there is provided a fiber matrix material having a fiber length; and a plurality of isolated fiber elements that are disposed in the fiber matrix, extending the fiber length, where the plurality is of a number greater than a number of isolated domains in a drawing preform of the fiber.