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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. [ABSTRACT FROM AUTHOR]

Upper critical field of polycrystalline δ-Mo1-xZrxN ( 0x0.3) thin films by sol-gel was investigated. It showed that the upper critical field was continuously improved with Zr doping content, and the improvement of10 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-Mo1-xZrxN thin films was presented, which will provide guidance for investigation about the vortex mechanisms of δ-Mo1-xZrxN thin films. [ABSTRACT FROM AUTHOR]

High room temperature coercivity CoFe2O4 (CFO) thin films are desirable in view of many applications, which is seldom achieved over 3 kOe in solution deposited CFO thin films. Herein, grain growth kinetic is investigated in the solution derived CFO thin films with coercivity larger than 4 kOe, showing a relaxation mechanism. The coercivity and magnetization increase initially and then decrease with increasing dwell time. The high coercivity is originated mainly from the critical grain size and the growth strain induced by the small crystallites and poorly developed grains. The results will provide a route to fabricate larger-area CFO thin films with high coercivity on silicon wafers by low-cost solution processing. [ABSTRACT FROM AUTHOR]

Epitaxial antiperovskite superconducting CuNNi3 thin films have been grown by chemical solution deposition. The film is a type II superconductor and shows a Tc of 3.2 K with a transition of 0.13 K. The Hc2(0) and ξ0 are estimated to be 8.1 kOe and 201 Å, respectively. [ABSTRACT FROM AUTHOR]

BiFeO3 films are prepared directly on n-type Si (100) substrates using chemical solution deposition method. The effects of individual-layer thickness via controlling the solution concentration on the texture, morphology, magnetic properties as well as the magnetoelectric properties are investigated. It was first observed that the derived films are the highly preferred c-axis oriented on Si substrates. With decreasing individual-layer thickness, the c-axis texture is improved due to preferred nucleation at the interfaces. The magnetization and the dielectric constant is increased and decreased with decreasing individual-layer thickness, respectively. It is interesting to observe that the magnetoelectric coupling is obviously enhanced with decreasing individual-layer thickness, which is beneficial for potential applications. [ABSTRACT FROM AUTHOR]

Transparent conducting p-type Bi2Sr2Co2Oy thin films have been first grown on SrTiO3 substrates by a chemical solution deposition, showing c-axis self-orientation. The figure of merit can reach as high as 800 MΩ-1, which is the highest value for p-type transparent conducting thin films by solution methods. [ABSTRACT FROM AUTHOR]

LaVO4 thin films have been deposited on Pt / Ti /SiO2 /Si substrates by pulsed laser deposition in order to explore the resistive switching (RS) behavior of the Au/LaVO4/Pt devices. It is found that the as-prepared Au/LaVO4/Pt devices stay in the low resistance state (LRS) and no electroforming process (forming-free) is needed to trigger fresh devices for the subsequent RS. Furthermore, the devices show excellent switching parameters such as a reproducible switching effect, a high resistance ratio of  ∼104 between the LRS and high resistance state (HRS), good endurance and retention characteristics, and non-overlapping switching voltages. The dominant conduction mechanisms are Ohmic conduction in the LRS and the lower voltage region of the HRS, and Poole–Frenkel emission in the higher voltage region of the HRS. The combination of temperature dependence of resistance, x-ray photoelectron spectroscopy, and model analysis suggests that the forming-free unipolar RS behavior can be explained by the formation and rupture of conical conducting filaments formed out of oxygen vacancies. These results may be important for practical application in nonvolatile resistive switching memory. [ABSTRACT FROM AUTHOR]

Ni0.5Zn0.5Fe2O4 particles with different particle sizes have been synthesized by sol-gel method. X-ray diffraction results show that all the samples are pure cubic spinel structure with their sizes ranging from 9 to 96 nm. The lattice constant significantly decreases with further increasing annealing temperature. The magnetic measurements show super paramagnetic nature below the particle size of 30 nm, while others show ferrimagnetic nature above the corresponding blocking temperature. The blocking temperature increases with the increase in particle size, which can be explained by Stoner-Wohlfarth theory. The saturation magnetization increases as the particle size increases, which can be explained by the cation redistribution on tetrahedral A and octahedral B sites and the domain wall motion. The variation of coercivity as a function of particle size is based on the domain structure. [ABSTRACT FROM AUTHOR]

In this article, the film of Sr0.775Y0.225CoO3-δ, which shows the highest ferromagnetic Curie temperature in perovskite ABO3-based cobaltates due to antiferrotype orbital order, was first prepared successfully on LaAlO3 (100) substrate using the simple chemical solution deposition (CSD) method. The results show that the derived film is (h00)-epitaxial, and the transport property is semiconductor like with room-temperature ferromagnetism (FM). The result will provide a feasible route to prepare Sr0.775Y0.225CoO3-d film with room-temperature FM using CSD with a low-cost and nonvaccum method. [ABSTRACT FROM AUTHOR]

Nanocrystalline CaMoO4 (CMO) thin films were fabricated on Si and glass substrates via the chemical solution deposition (CSD) method. From x-ray diffraction, atomic force microscopy and Fourier transform infrared spectra results, relatively smooth Scheelite-type CMO thin films can be fabricated within the annealing temperature range from 400 to 700 °C. The band gap is 4.18 eV calculated from the optical transmission spectra and the photoluminescence (PL) emission spectra show that the CMO thin films on Si have a broad green emission band centred at 490 nm. Our experimental results show that the CSD method is an alternative method to prepare nanocrystalline CMO thin films with a great PL property at low annealing temperatures. [ABSTRACT FROM AUTHOR]