We have discovered a new high-T c oxide superconductor of the Bi-Sr-Ca-Cu-O system without any rare earth element. The oxide BiSrCaCu2O x has T c of about 105 K, higher than that of YBa2Cu3O7 by more than 10 K. In this oxide, the coexistence of Sr and Ca is necessary to obtain high T c.

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A wire-conductor fabrication method has been developed for Cu–Ag alloys containing 2–60 at. % Ag where high strength and high conductivity conductors are obtained by cold working combined with intermediate heat treatment. The intermediate heat treatment is repeated 3–4 times at 350–450 °C for 1–2 h at appropriate stages of reduction of area. The optimized Cu-16 at. % Ag alloy wire with 99% reduction of area showed a tensile strength of 1000 MPa and an electrical conductivity of 80% IACS at room temperature. This suggests that the wires fabricated may be very promising for high-field pulsed magnet use.

Ink-jet printable thin-film transistors (TFTs) on flexible plastic substrates are an important focus of research because present silicon-based electronics cannot realize such devices. In the present study, we fabricated single-walled carbon nanotube (SWCNT) TFTs on plastic substrates using the ink-jet printing method, and realized high-on/off current ratio (10 4 ) and flexibility, respectively. The present study therefore represents a major step towards ''flexible SWCNT electronics''.

The epitaxial lateral overgrowth (ELO) technique is an important technology for improving the characteristics of GaN-based laser diodes (LDs). The photoluminescence intensities from GaN and GaInN multiple quantum well active layers in the ELO-GaN wing region were found to be higher than those in the seed region. This indicates that the density of dislocations in the wing region could be reduced significantly. This is evidenced by dislocation densities of less than 106 cm-2 as determined from transmission emission microscopy and etching-pit-density measurements. The cleaved facets of LDs on ELO-GaN and sapphire were observed by atomic forced microscopy. Although the roughness of GaN cleaved facets on sapphire were high (Ra>10 nm), the roughness in the ELO-GaN wing region was found to be as smooth as that of GaAs cleaved facet (Ra<1 nm). The characteristics of LDs on ELO-GaN were found to be superior to those on sapphire as a result of smoother facets and lower dislocation densities.