FeSeTe nanobridges of different widths have been fabricated on MgO substrates using focused ion beams. These nanobridges exhibit the Josephson effects. The current-voltage curves of junctions with 248–564 nm wide follow the resistively and capacitatively shunted junction model. Shapiro steps under microwave radiation were clearly observed in these nanobridges. The products of the critical current and normal state resistance (I c R n) are remarkably high. The temperature dependence of I c R n product followed the Ambegaokar-Baratoff (A-B) relation. The value of energy gap of FeSeTe calculated from the A-B relation is 3.5kBTc. The nanobridge junctions have a strong potential for high frequency applications

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The preparation of BFO films by sputtering at a temperature as low as 450 °C on glass and commercial Pt/Ti/SiO2/Si(001) substrates have been studied. The underlayers with different orientations were prepared on the glass substrates including strongly textured Pt(111) and L10-FePt(001) induced by rapid thermal annealing process. Isotropic perovskite BFO grains with size of about 200 nm formed on the commercial substrates, showing larger surface roughness. Pt(111) suppresses BiFeO3 phase. Single phase perovskite BFO with strong (001) texture, reduced surface roughness and fine grain size was formed on the L10-FePt(001) buffer layer. Considerable enhancement of ferroelectric properties was achieved as compared to the films grown on commercial substrate.