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A typical compact pulsed magnet coil wound from copper and Zylon fiber was fabricated with optical fiber sensors embedded at different places in the Zylon layers. Measurements of deformation have been carried out during winding, cooling and with magnetic field pulses up to 10 T at room temperature and 41 T at 77 K. The results are in agreement with the calculated strain distribution by taking into account the anisotropy of fiber/epoxy composites. [ABSTRACT FROM PUBLISHER]

We have studied a high field pulsed superconductor with high elastic modulus fiber reinforcement. We call the conductor Fiber Reinforced Superconductor (FRS). We have succeeded in making a sputtering target which consists of reacted Nb/sub 3/Sn single material by powder metallurgy. Nb/sub 3/Al superconductor is well known as a candidate for superconducting magnets for fusion reactors because of good properties of mechanical stress and irradiation toughness. To overcome the difficulty of fabricating into superconducting wire, we have made a single sputtering target of Nb-Al compound by powder metallurgy. Thin Nb/sub 3/Al films on MgO substrate were made using this target. Experimental results for these films are presented. [ABSTRACT FROM PUBLISHER]

We have fabricated by SNEP process Nb/Al/NbN/AlN/NbN Josephson junctions with the gap voltage V/sub g/=2/spl Delta//e/spl ap/4.0 mV, subgap leakage R/sub sg//R/sub n//spl ap/6.0, current density measured at the gap current rise J/sub g//spl ap/1.5 kA/cm/sup 2/. The (111)-textured NbN with transition temperature T/sub c//spl ap/16 K have been deposited at ambient substrate temperature. Phase composition and structure of the NbN films were investigated by X-ray diffraction analysis (XRD). It was found that the films have a structure close to the cubic /spl delta/-NbN (JCPDS card N38-11556) and the phase composition and intrinsic stress in NbN depend on Ar and N/sub 2/ partial pressure during DC magnetron sputtering. Cross-sectional TEM analysis showed that in-situ deposition of thin Al layer in the base Nb/Al/NbN electrode provides effective planarization of its surface and the result in improvement of tunnel junction parameters. [ABSTRACT FROM PUBLISHER]

A new substrate material LSAT, a 30/70 mole % solid solution between LaA103 and Sr2AITaO6, has been prepared for the purposes of eliminating twinning, strain and non-isotropic microwave properties found in pure LaA103 substrates. At 300 K and 30/70 mole %, LSAT is cubic with lattice parameter of 7.737 Å. The dielectric properties of single crystal LSAT (30/70 mole %) substrates have been measured at 10 GHz and 300 K and determined to be: dielectric constant ε=22.5; and, loss tangent tan(δ) ⩽ 10-3. High quality c -axis oriented high critical temperature superconducting (HTSC), YBa2Cu307-δ (YBCO), thin films have been deposited on (001) single crystal LSAT substrates. The crystal quality of these films is excellent as evidenced by the full width half maximum (FWHM) rocking curve widths of typically 300 arc-seconds. Critical current densities (as measured using magnetization) are about 4 × 106 A/cm2 at 10 K. Microwave film properties include an onset transition temperature (Tc) higher than 91 K, transition width (ΔTc) less than 5 K, surface resistance RS lower than copper (30 mω) at 85 K and 35 GHz for a film of thickness 2500 Å. [ABSTRACT FROM PUBLISHER]