Browsing by Author "Joannopoulos, J. D."

Now showing 1 - 3 of 3

Open Access
Kilometer-long ordered nanophotonic devices by preform-to-fiber fabrication
(Institute of Electrical and Electronics Engineers, 2006) Bayındır, Mehmet; Abouraddy, A.F.; Shapira O.; Viens J.; Saygin-Hinczewski, D.; Sorin, F.; Arnold, J.; Joannopoulos, J. D.; Fink, Y.
A preform-to-flber approach to the fabrication of functional fiber-based devices by thermal drawing in the viscous state is presented. A macroscopic preform rod containing metallic, semiconducting, and insulating constituents in a variety of geometries and close contact produces kilometer-long novel nanostructured fibers and fiber devices. We first review the material selection criteria and then describe metal-semiconductor-metal photosensitive and thermally sensitive fibers. These flexible, lightweight, and low-cost functional fibers may pave the way for new types of fiber sensors, such as thermal sensing fabrics, artificial skin, and large-area optoelectronic screens. Next, the preform-to-fiber approach is used to fabricate spectrally tunable photodetectors that integrate a photosensitive core and a nanostructured photonic crystal structure containing a resonant cavity. An integrated, self-monitoring optical-transmission waveguide is then described that incorporates optical transport and thermal monitoring. This fiber allows one to predict power-transmission failure, which is of paramount importance if high-power optical transmission fines are to be operated safely and reliably in medical, industrial and defense applications. A hybrid electron-photon fiber consisting of a hollow core (for optical transport by means of a photonic bandgap) and metallic wires (for electron transport) is described that may be used for transporting atoms and molecules by radiation pressure. Finally, a solid microstructured fiber fabricated with a highly nonlinear chalcogenide glass enables the generation of supercontinuum light at near-infrared wavelengths.
Open Access
Large-scale optical-field measurments with geometric fibre constructs
(Nature Publishing Group, 2006) Abouraddy, A. F.; Shapira, O.; Bayındır, Mehmet; Arnold, J.; Sorin, F.; Hinczewski, D. S.; Joannopoulos, J. D.; Fink, Y.
Optical fields are measured using sequential arrangements of optical components such as lenses, filters, and beam splitters in conjunction with planar arrays of point detectors placed on a common axis1. All such systems are constrained in terms of size, weight, durability and field of view. Here a new, geometric approach to optical-field measurements is presented that lifts some of the aforementioned limitations and, moreover, enables access to optical information on unprecedented length and volume scales. Tough polymeric photodetecting fibres drawn from a preform2 are woven into light-weight, low-optical-density, two- and three-dimensional constructs that measure the amplitude and phase of an electromagnetic field on very large areas. First, a three-dimensional spherical construct is used to measure the direction of illumination over 4π steradians. Second, an intensity distribution is measured by a planar array using a tomographic algorithm. Finally, both the amplitude and phase of an optical wave front are acquired with a dual-plane construct. Hence, the problem of optical-field measurement is transformed from one involving the choice and placement of lenses and detector arrays to that of designing geometrical constructions of polymeric, light-sensitive fibres.
Open Access
Thermal-sensing fiber devices by multimaterial codrawing
(Wiley - V C H Verlag GmbH & Co. KGaA, 2006) Bayındır, Mehmet; Abouraddy, A. F.; Arnold, J.; Joannopoulos, J. D.; Fink, Y.
Thermal sensing provides important information on the state of many physiological, chemical, and physical systems. However, the problem of continuously monitoring and detecting a thermal excitation over very large areas (100 m2) with high resolution (1 cm2) still remains. A solution to this problem is presented here in which a fiber (see figure) senses heat along its entire length and generates an electrical signal.