We investigate electromagnetic scattering from nanoscale wires and reveal the emergence of a family of exotic resonances for source waves close to grazing incidence. These grazing resonances have a much higher Q-bandwidth product and thus, a much higher Q factor and broader bandwidth than the pure plasmonic resonances found in metal nanowires. Furthermore, these grazing resonances are much less susceptible to material losses than surface plasmon resonances. Contrary to the process of exciting surface plasmon resonances, these grazing resonances can arise in both dielectric and metallic nanowires and appear near to the cutoff wavelength of the circular waveguide. This peculiar resonance effect originates from the excitation of long range guided surface waves through the interplay of coherently scattered continuum modes coupled with first-order azimuthal propagating modes of the cylindrical nanowire. These first-order cyclic Sommerfeld waves and associated cyclic Sommerfeld resonances revealed here opens up the possibility of an alternative scheme of enhanced fields with a better merit (higher Q-bandwidth product and lower loss) than conventional surface plasmon resonances in the nano-regime. This nanowire resonance phenomenon can be utilized in broad scientific areas, including: metamaterial designs, nanophotonic integration, nanoantennas, and nanosensors.

A survey of possible applications of high-temperature superconductors (HTS's) to antennas and antenna feed networks is present?. The frequency range of consideration is 1 MHz to 100 GHZ: Three antenna application areas seem appropriate for HTS material: electrically small antennas and their matching networks; feed and matching networks for compact arrays with enhanced directive gain (superdirective arrays); and feed networks for millimeter-wave arrays. Preliminary experimental results are presented on YBaCuO and TIBaCaCuO 500 MHz half-loop antennas that show an increase in radiation efficiency (compared with a copper antenna at the same temperature) by a factor of 5 for the HTS antennas.

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PLufr r4atigbvrdsa for *a wc~bcx im4otiUorrvm a 95ff*d to tirwor I how ur~v~ pein "he tasltrawn w.s0wm ~d oom.qgitwrvV"a rrriawti.Md Vi. d~la ibtiod. and ouv and (wr-iv..gthe 0v 4~no .ofwudori Send conivirts rogwdng the tnwdme eaftae or mniy other m* df ie O~doiiv at uiw o~nit. vwkjde eu~ptiw for riaduorg the buriM,. to Wmehrgton H~wwdtw. Servmx D-owa. for anwtdtmb Operem end Peoporw. 1216 .etiiaorrA Osnu Higrm-W. Sute 1204. "ohtn. VA 22O 4 3u. aid to the OfIce of Meugeaaemm end Budget. Paparmen Reduiono Projec (0704-at198). Wastegon. DC 206GM A Statement: Distribution Unlimited 13. ASSTRAC.T (Maactwn M.Owors) (U) We present a detailed electromagnetic analysis of an electrically small colocated electric dipole arnd magnetic iocp antenna array. This antenna is the simplest example of the Grimes multipolle class of antenna arrays. We have determined that since the interaction term between the two elements disappears from the radial complex power, we were able to set the radial react~ance to zero by choosing appropriate current magnitudes and phases on the array elements. By driving the two elemnents in quadrature, we obtained a much increased radiation intensity and directivity as wel' as increased radiated power. M. SBJEC TERS 15 NUMBER Of PAGES Antennas, Mutua! Impedar.:e, Electric Dinole, Arrays, Muhtipoles, Magnetic Loop 3 17. SECURtITY CLASSI1CA11ON 16. SECURITY CLASSIRCATION I&. SECURITY CLASSIRCATION 210 UNIATION OF' ABSTRACT