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Contamination‐free TiNx was prepared and the lattice parameter (a0)–nitrogen content (x) relation determined. The result can be expressed as a0 = 4.1925 + 0.0467x (in Å) in the range 0.605 ≤x≤ 0.999. Density measurement showed that no titanium vacancies existed in the lattice.

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Fluctuation-free electron emission is obtained from MIM (Al-Al2O3-Au) cathodes. The Al2O3 layer is fabricated by anodic oxidation with a reduced electrolysis current density, i.e., a reduced oxidation rate. The slow oxidation process improves the insulating effect of the Al2O3 layer, and enables the MIM cathodes to operate in the non-formed state. The fluctuation-free emission is reproducible when the diode voltage is cut off instantaneously. With a thin Al2O3 layer, the diode voltage reguired for the cathode operation is reduced to values slightly above the work function of the top electrode.

We propose a novel fabrication technique based on the formation of a Nb protective layer on a MgB2 thin film and high-temperature post-annealing to increase the critical current density (J c) of MgB2 films under an external magnetic field. Analyses of the crystal structure and the composition of the processed MgB2 films confirmed the suppression of the evaporation and oxidation of Mg by high-temperature annealing above 550 °C. The MgB2 film annealed at 650 °C exhibited a J c of 1.62 MA cm−2 under 5 T, which is the highest reported value for MgB2 films, wires, and bulk samples to date.