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High coercivity CoFe2O4 (CFO) thin films with large-area are very desirable for applications. Here, we report La0.7Sr0.3MnO3 (LSMO) layer decoration effects on coercivity in CFO thin films by solution processing. With LSMO layer decoration, the coercivity increases initially and then decreases with increasing LSMO layer thickness. Strain induced by the mismatched thermal expansion coefficient and magnetostrictive coefficient as well as the interfacial magnetic exchange coupling between CFO and LSMO are investigated. The room temperature out-of-plane and in-plane coercivity reached 7.6 and 4.9 kOe, respectively, are obtained, which are the highest values in solution derived CFO thin films. The improved coercivity is beneficial for applications and provides a facile route to enhance coercivity of CFO thin films through surface modification by soft magnetic layers.

Upper critical field of polycrystalline δ-Mo1-xZrxN (0 ≤ x ≤ 0.3) thin films by sol-gel was investigated. It showed that the upper critical field was continuously improved with Zr doping content, and the improvement of ∼10 T in upper critical field was mainly attributed to the combined effects of obvious enhancements in normal-state resistivity with slight changes in Tc, obvious decrease in crystallite/grain size and enhanced microstrains. Flux jump was observed in low-level doped thin films due to enhanced critical current density by Zr doping. Finally, the vortex phase diagram of δ-Mo0.95Zr0.05N thin films was presented, which will provide guidance for investigation about the vortex mechanisms of δ-Mo1-xZrxN thin films.

Different resistive switching has been observed in the Au/BiFeO3/Pt structure composed with the BiFeO3 (BFO) thin films annealed at different temperature for different dwell time. Resistive switching decreases and disappearances with increasing annealing temperature, while reappear with prolonging dwell time. The evolution in the resistive switching is understand by the polarization modulated interfacial barriers for the low temperature annealing BFO films, oxygen vacancies rectifying interfacial depletion layer barriers for the high temperature and long time, and p-n junction for the films annealed for the longest time at high temperature.