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Hu, X., Dauler, E. A., Kerman, A. J., Yang, J. K. W., White, J. E., Herder, C. H., et al. (2009). Using surface plasmons to enhance the speed and efficiency of superconducting nanowire single-photon detectors. In Proceedings of the Conference on Lasers and Electro-Optics, 2009 and 2009 Conference on Quantum electronics and Laser Science Conference (pp. 1–2).
Abstract: We report our design and fabrication of superconducting nanowire single-photon detectors integrated with gold plasmonic nanostructures, which can enhance the absorption of TM-polarized light, and can enlarge the effective area without sacrificing detector speed.
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Puscasu, I., & Boreman, G. D. (2001). Theoretical and experimental analysis of transmission and enchanced absorption of frequency selective surfaces in the infrared. In Proc. SPIE (Vol. 4293, pp. 185–190).
Abstract: A comparative study between theory and experiment is presented for transmission through lossy frequency selective surfaces (FSSs) on silicon in the 2 – 15 micrometer range. Important parameters controlling the resonance shape and location are identified: dipole length, spacing, impedance, and dielectric surroundings. Their separate influence is exhibited. The primary resonance mechanism of FSSs is the resonance of the individual metallic patches. There is no discernable resonance arising from a feed-coupled configuration. The real part of the element's impedance controls the minimum value of transmission, while scarcely affecting its location. Varying the imaginary part shifts the location of resonance, while only slightly changing the minimum value of transmission. With such fine-tuning, it is possible to make a good fit between theory and experiment near the dipole resonance on any sample. A fixed choice of impedance can provide a reasonable fit to all samples fabricated under the same conditions. The dielectric surroundings change the resonance wavelength of the FSS compared to its value in air. The presence of FSS on the substrate increases the absorptivity/emissivity of the surface in a resonant way. Such enhancement is shown for dipole and cross arrays at several wavelengths.
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Lee, B. G., Doany, F. E., Assefa, S., Green, W., Yang, M., Schow, C. L., et al. (2010). 20-μm-pitch eight-channel monolithic fiber array coupling 160 Gb/s/channel to silicon nanophotonic chip. In Conf. OFC/NFOEC (pp. 1–3).
Abstract: A multichannel tapered coupler interfacing standard 250-μm-pitch low-NA polarization-maintaining fiber arrays with ultra-dense 20-μm-pitch high-NA silicon waveguides is designed, fabricated, and tested, demonstrating coupling losses below 1 dB and injection bandwidths of 160 Gb/s/channel.
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Kopp, V. I., Churikov, V. M., Zhang, G., Singer, J., Draper, C. W., Chao, N., et al. (2007). Chiral fiber gratings: perspectives and challenges for sensing applications. In Proceedings of Third european workshop on optical fibre sensors (Vol. 6619, pp. 66190B–(pp. 1–8)).
Abstract: Chiral fiber gratings are produced in a microforming process in which optical fibers with noncircular or nonconcentric cores are twisted as they pass though a miniature oven. Periodic glass structures as stable as the glass material itself are produced with helical pitch that ranges from under a micron to hundreds of microns. The geometry of the fiber cross section determines the symmetry of the resulting structure which in turn determines its polarization selectivity. Single helix structures are polarization insensitive while double helix gratings interact only with a single optical polarization. Both single and double helix gratings may act as a fiber long period grating, coupling the core and cladding modes. The coupling is manifested in a series of narrow dips in the transmission spectrum. The dip position is sensitive to fiber elongation, twist and temperature, and to the refractive index of the surrounding medium. The suitability of chiral gratings for sensing pressure, temperature and liquid levels is investigated. Polarization insensitive single helix silica glass gratings display excellent stability up to temperatures of 6000C, while a pressure sensor with dynamic range of nearly 40 dB is demonstrated in polarization selective double helix gratings.
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Khosropanah, P., Merkel, H., Yngvesson, S., Adam, A., Cherednichenko, S., & Kollberg, E. (2000). A distributed device model for phonon-cooled HEB mixers predicting IV characteristics, gain, noise and IF bandwidth. In Proc. 11th Int. Symp. Space Terahertz Technol. (pp. 474–488). University of Michigan, Ann Arbor, MI USA.
Abstract: A distributed model for phonon-cooled superconductor hot electron bolometer (HEB) mixers is given, which is based on solving the one-dimensional heat balance equation for the electron temperature profile along the superconductor strip. In this model it is assumed that the LO power is absorbed uniformly along the bridge but the DC power absorption depends on the local resistivity and is thus not uniform. The electron temperature dependence of the resistivity is assumed to be continuous and has a Fermi form. These assumptions are used in setting up the non-linear heat balance equation, which is solved numerically for the electron temperature profile along the bolometer strip. Based on this profile the resistance of the device and the IV curves are calculated. The IV curves are in excellent agreement with measurement results. Using a small signal model the conversion gain of the mixer is obtained. The expressions for Johnson noise and thermal fluctuation noise are derived. The calculated results are in close agreement with measurements, provided that one of the parameters used is adjusted.
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