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Domain walls in ferroelectric materials attract great interest since they can possess fascinating functionalities. Therefore, it is very important to modulate domain structures. Our recent experiments showed that oxygen vacancy plates could induce charged domain walls with different types. However, the detailed transition behavior between different charged domain walls was not explored. In this work, systematical phase field simulations were performed to reveal the evolution of domain structures with the size and charge density of the oxygen vacancy plate. These results could provide a route to build complex patterns of charged domain walls. [ABSTRACT FROM AUTHOR]

Presents information on a study which performed magneto-optical experiments on free and bound electrons in gallium (Ga) nitrogen (N) films and GaN/aluminum GaN heterojunctions. Experimental procedure; Results and discussion; Conclusion.

Flux-closure domain structures in ferroelectric thin films are considered to have potential applications in electronic devices. It is usually believed that these structures are stabilized by the depolarization field and the contact with electrodes tends to screen the depolarization field and may limit their formation. In this work, the influence of oxide electrodes (SrRuO3 and La0.7Sr0.3MnO3) on the formation of flux-closure domains in PbTiO3 thin films deposited on (110)-oriented GdScO3 substrates by pulsed laser deposition was investigated by Cs-corrected transmission electron microscopy. It is found that periodic flux-closure domain arrays can be stabilized in PbTiO3 films when the top and bottom electrodes are symmetric, while a/c domains appear when asymmetric electrodes are applied. The influence of asymmetric electrodes on the domain configuration is proposed to have a connection with their different work functions and conductivity types. These results are expected to shed light on understanding the nature of flux-closure domains in ferroelectrics and open some research possibilities, such as the evolution of these structures under external electric fields. [ABSTRACT FROM AUTHOR]

Presents a study that investigated the static thermomagnetic recording properties of manganese-bismuth-aluminum thin films. Analysis of the magnetic-domain structures of the thin films; Examination of the write/erase cycles on the thin films; Effect of annealing on the write/erase performance of the thin films.

Presents a study that produced manganese (Mn)-bismuth (Bi)-aluminum thin films by sequential evaporation of the constituents. Temperature dependencies of the Kerr rotation angle; Composition dependencies of the absolute reflectivity; Factor that will make thin films retain the pure MnBi hexagonal structure.

Exotic domain states, like vortex, offer the promise of superior properties and the potential disclination strain is a key factor for their formation in ferroelectrics. Here we show that large scale arrays of four-state vortex domains can be obtained in rhombohedral BiFeO3 thin films grown on PrScO3 substrates by pulsed laser deposition. Cs-corrected scanning transmission electron microscopy demonstrates that each vortex domain is comprised of four ferroelectric variants with two 180° domain walls and two 109° domain walls. Atomic mappings of the lattice distortions unit cell by unit cell reveal that the cores of the vortex might be charged. The strains are mainly concentrated on domain walls. The formation mechanism of such large scale vortex-like states was discussed. [ABSTRACT FROM AUTHOR]

Anomalous Hall effect (AHE) in ferrimagnetic Mn4N epitaxial films grown by molecular-beam epitaxy is investigated. The longitudinal conductivity σxx is within the superclean regime, indicating Mn4N is a highly conducting material. We further demonstrate that the AHE signal in 40-nmthick films is mainly due to the extrinsic contributions based on the analysis fitted by ρAH = σ'ρxx0 + bρ²xx and σAH ∝ σxx. Our study not only provide a strategy for further theoretical work on antiperovskite manganese nitrides but also shed promising light on utilizing their extrinsic AHE to fabricate spintronic devices. [ABSTRACT FROM AUTHOR]

ZnMgO thin films deposited on Si (111) substrates by pulsed laser deposition at 300°C were annealed at different temperatures from 400 to 800°C in air. Non-polar films with (110) orientation have been obtained. The thin film annealed at 500°C shows the co-existence of (002), (200) and (110) orientations according to X-ray diffraction observation, which illustrated that Mg has been incorporated into ZnO. Scanning electron microscopy images and energy dispersive X-ray revealed the variation of surface morphology and element content. The largest band gap value has been determined to be 4·31 eV when the film was annealed at 700°C. The typical peaks of Zn-O and Mg-O bonds were observed in the IR spectrum. The shift of UV peaks in photoluminescence spectra emerged due to the increase in Mg doping as the annealing temperature increases. [ABSTRACT FROM AUTHOR]

Metal–ferroelectric–insulator–semiconductor structures using LaAlO3 (LAO) layers as an insulating barrier have been investigated. LAO films were deposited on n-Si substrates by low-pressure metalorganic chemical vapor deposition (MOCVD). SrBi2Ta2O9 (SBT) films were prepared as ferroelectric layers at a low processing temperature of 650 °C by a metalorganic decomposition method. The MOCVD-derived LAO buffer layer shows an amorphous structure, relatively high dielectric constant, and good electrical properties. Au/SBT/LAO/n-Si exhibits a larger counterclockwise C–V memory window of 3.7 V and a lower leakage-current density of 2.5×10-8 A/cm2 at an applied voltage of 10 V. It has been confirmed that the hysteresis loop is caused by ferroelectricity. The Auger electron spectrometry depth profile indicates that the introduction of the LAO buffer layer prevents the interfacial diffusion between SBT and the Si substrate effectively and improves the interface quality. [ABSTRACT FROM AUTHOR]

Comments on a study on the dewetting morphology of polystyrene films. Characteristic of the surface fluctuations that occurred in the study; Number of holes identified in the films; Information on the spinodal rupturing process.