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Intrinsic Josephson effect devices from Tl2Ba2CaCu2O8 (Tl-2212) thin films were investigated. The device was produced by epitaxially growing a Tl-2212 thin film on a LaAlO3 substrate with the surface cut at a small angle to the LaAlO3(001) plane, and by patterning a microbridge in the proper direction. The I–V characteristics of the microbridges exhibit large hysteresis at low temperatures, and the temperature dependence of the critical current Ic(T) is in good agreement with the theoretical Ambegaokar–Baratoff relation for superconductor–insulator–superconductor (SIS) junctions. The I–V curves also show multibranches for longer microbridges.

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We employed terahertz (THz) time-domain spectroscopy (TDS) imaging technology, a new nondestructive testing method, to detect the inclusions of glass-fiber-reinforced polymer (GFRP) composites. The refractive index and absorption coefficient of two types of GFRP composites (epoxy GFRP composites and polyester GFRP composites) were first extracted, and GFRP composites with Teflon inclusions were examined, including an epoxy GFRP solid panel with a smaller Teflon inclusion hidden behind a larger Teflon inclusion, and polyester GFRP solid panels with Teflon inclusions of various sizes, at different depths. It was experimentally demonstrated that THz TDS imaging technology could clearly detect a smaller inclusion hidden behind a larger inclusion. When the reflected THz pulse from the inclusion did not overlap with that from the front surface of the sample, removal of the latter before Fourier transform was shown to be helpful in imaging the inclusions. With sufficiently strong incident THz radiation, inclusion insertion depth had little impact on the ability of the THz wave to detect inclusions. However, as the thickness of the inclusion became thinner, the inclusion detection ability of the THz wave deteriorated. In addition, with a combination of reflected C-scan imaging and B-scan imaging using the reflected time-domain waveform, both the lateral sizes and locations of the inclusions and the depths and thicknesses of the inclusions were clearly ascertained.