We have acquired positive results in a controlled study to investigate the effects of substrate surface modification on the growth-induced flux-pinning nanostructures in ${\mathrm{YBa}}_2{\mathrm{Cu}}_3{\mathrm{O}}_{7-\delta }$ (YBCO) films. Nanoscale iridium (Ir) particles were applied to single-crystal ${\mathrm{SrTiO}}_3$ substrate surfaces using dc-magnetron sputtering. Superconducting properties of YBCO films grown on the Ir-modified substrates, measured by transport and magneto-optical imaging, have shown substantial improvement in the critical current densities $\left(J_c\right)$ at 77 K over those on untreated, control substrates. Results also show a nearly uniform enhancement of $J_c$ over all orientations of magnetic field. Present results are found to be consistent with cross-sectional transmission electron microscopy investigations. Ultimately, the objective of this approach is to produce enhancements in the properties of coated conductors by a simple pretreatment of the substrate surface.

A coating that embodies omnidirectional optical properties over a wide range of wavelengths and possessing specific wetting capabilities is established on glass platforms.

Large-size vertical β- ${Ga_{2}O_{3}}$ Schottky barrier diodes (SBDs) with various device areas were demonstrated on a Si-doped n-type drift layer grown by hydride vapor phase epitaxy (HVPE) on bulk Sn-doped (001) n-type β- ${Ga_{2}O_{3}}$ substrate. In this study, the devices have two circular contacts with a diameter of 1500 μm and 500 μm and two square contacts with dimensions of 1600×1600 μm² and 800×800 μm², corresponding to the area of 0.2×10^-2 cm² (the smallest device), 0.6×10^-2 cm², 1.8×10^-2 cm², and 2.6×10^-2 cm² (the largest device). The breakdown voltage (BV) was determined to be -261 V for the largest device and -427 V for the smallest device. Also, the ideality factor (η) of vertical ${Ga_{2}O_{3}}$ SBDs with different device areas exhibited the same value of 1.07, except for the largest device area of 2.6×10^-2 cm² with an ideality factor of 1.21. At an applied forward bias of V_F=2 V, the specific on-state resistance (R_onA) of all the ${Ga_{2}O_{3}}$ SBDs remains relatively low with values ranging from 1.43×10^-2 Ωcm² to 7.73×10^-2 Ωcm². The measured turn-on voltage (V_on) of all the SBDs remains low with a narrow distribution.