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Domain engineering is an active field of research that aims to enhance the functional properties of ferroelectric materials for various applications. This work presents a voltage-free method for fabricating topological superdomain arrays in 0.72Pb(Mg1/3Nb2/3)O3-0.28PbTiO3 (PMN-28PT) crystals. During the cooling process from high-temperature paraelectric phase to room temperature ferroelectric phase, the out-of-plane polarization of PMN-28PT crystals in contact with aluminum can be fully regulated downward, attributed to the difference in the work function of aluminum and PMN-28PT. In conjunction further with photolithography and ultraviolet light illumination, it is easy to obtain periodic strip domain structures with alternating up and down polarization. Moreover, this method can also control in-plane polarization, resulting in a large-scale central divergent/convergent topological superdomain array. These findings provide insights into ferroelectric domain engineering and have implications for the development of electromechanical, piezoelectronic, and photonic devices. [ABSTRACT FROM AUTHOR]

Polycrystalline PbZrO3 films with a preferred orientation were fabricated via the metal-organic decomposition method. For heat-treated PbZrO3 films, the P-E hysteresis loops, dielectric spectra, and I-V curves show interesting changes with time, which strongly suggest the coexistence of antiferroelectric and ferroelectric phases at room temperature. Based on the easy transition between these two phases, the electric properties of the films become tunable. A dielectric tunability of about 50.2% below 8.2 V makes it a promising low working-voltage dielectric tunable material, and the significant current change of four orders of magnitude indicates potential application as a voltage-controlled rheostat. [ABSTRACT FROM AUTHOR]

0.7Pb(Zr0.52Ti0.48)O3-0.3Pb(Ni1/3Nb2/3)O3 (abbreviated as PZT-PNN) ceramics were prepared using the solid-state reaction method. The results reveal that ferroelectric and anti-ferromagnetic orderings coexist (multiferroicity) in PZT-PNN ceramics. Furthermore, the abnormal behavior of dielectric constant and loss observed at Néel temperature gives an evidence of the coupling between the ferroelectric and anti-ferromagnetic orderings (magnetoelectric coupling). The ferroelectric loops become slimmer with increasing temperature and the remnant polarization persists up to above the temperature of dielectric maximum (Tm), indicates a lead-induced ferroelectric behavior. [ABSTRACT FROM AUTHOR]

Perovskite BiFeO3 films with various thicknesses were prepared on Pt/Ti/SiO2/Si substrates by metal organic decomposition method. It was found that, with the film thickness increasing from 35 to 120 nm, the grain and ferroelectric domain size slightly increased, while the saturation magnetization Ms abruptly decreased. For the further increase of film thickness, Ms decreased slowly and the magnetization of unit area exhibited a fluctuation behavior. Moreover, the magnetic anisotropy degenerated with the increase of film thickness. The possible causes for the thickness effects were discussed. [ABSTRACT FROM AUTHOR]

The LiNbO3 crystals were polarized at fixed points and characterized by means of scanning probe microscope. The growth evolution and the decay process of the fabricated domains were carefully studied. Two critical radii rC and Rc that determine a different decay behavior of domains were put forward, where rC is considered to correspond to the point when the domains just penetrate the crystal. Those domains with radius larger than rC could exist beyond 5 days, those between rC and Rc experienced a distinct metastable state before completely disappearing, while those smaller than Rc were even invisible under piezoresponse force mode. [ABSTRACT FROM AUTHOR]

BiFeO3 (BFO)/Bi3.25La0.75Ti3O12 (BLT) films were prepared on (111) Pt/Ti/SiO2/Si substrates via metal organic decomposition method. The multiferroic and dielectric properties of the films were studied. It was found that the ferroelectric polarization and dielectric constant of the films were enhanced by introducing BLT as a barrier layer between BFO and Pt bottom electrode, while the ferromagnetism of BFO was not influenced. More interestingly, the films showed dielectric relaxor behavior, and the possible causes of which were discussed. [ABSTRACT FROM AUTHOR]

The LiNbO3 crystal was polarized and characterized by the piezoresponse force mode of scanning probe microscope. By using the Kolmogorov-Avrami-Ishibashi [Izv. Akad. Nauk, USSR: Ser. Math. 3, 355 (1937); J. Chem. Phys. 8, 212 (1940); J. Phys. Soc. Jpn. 63, 1031 (1994); 63, 1601 (1994)] theory to analyze the relaxation process after domain switching, it was found that (1) the percent of final switched domains after poling increased with the enhancing poling voltage, (2) the nucleation time was a constant to a certain sample, (3) the dimension of domain growth decreased with the enhancing poling voltage, and (4) the relaxation time had a maximum at a medial voltage. The corresponding mechanism for domain switching was discussed, which is hopefully useful for domain engineering. [ABSTRACT FROM AUTHOR]

Polycrystalline Bi1-xNdxFeO3 (x=0–0.15) thin films were prepared on (111) Pt/Ti/SiO2/Si substrates via metal organic deposition method. The effect of Nd dopant on the structural, electric, and magnetic properties was studied. It was found that the ferroelectric polarization and saturation magnetization of the films were enhanced by appropriate Nd doping due to the structural distortion and the suppressed cycloidal spin structure. Meanwhile, Nd-doped BiFeO3 thin films exhibited magnetic anisotropy because of the magnetocrystalline anisotropy. [ABSTRACT FROM AUTHOR]

The effect of poling on the switching properties of SrBi[sub 2]Ta[sub 2]O[sub 9] films was investigated via the technique of switching current testing. The samples with 660 nm thickness were poled under dc voltage ranging from 1 to 8.25 V, and for different duration from 1 to 80 min. After poling, both the net-switched charge and switching time first jumped to higher values, then decreased with the elapse of time. The decreases were separated into two regimes, a fast and slow regime. The change of net-switched charge and switching time with poling voltage and poling time showed nonmonotonic behavior. These results were explained by the change of domain kinetics and the redistribution of charge carriers under both the applied and depolarization field. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Bi0.8La0.2FeO3 (BLFO) films are deposited directly on low-resistance Si (100) substrates by the pulsed laser deposition method. Compared with the typical hysteresis loops of ferroelectric films, those of the BLFO/Si samples, with almost horizontal upper and lower ends, severely shrink in the center part, and the coercive voltage is extremely small. A systematic analysis of the dielectric and ferroelectric characteristics reveals that a p–n junction forms between BLFO and Si, with oxygen vacancies accumulating near the interface. The polarization switching is accompanied by the change of the interface barrier and the migration of charged defects. This work provides a reference for the direct growth of ferroelectric films on silicon substrates and is of great significance for the development of the silicon-based electronic devices. [ABSTRACT FROM AUTHOR]

PbZrO3-xSrTiO3 solid solution thin films were designed and fabricated by a metal organic decomposition method, and their structural, ferroelectric, and energy storage characteristics were investigated systematically. It is found that the incorporation of SrTiO3 not only gradually transforms PbZrO3 from antiferroelectrics to relaxor ferroelectrics but also obviously increases its breakdown strength. Large ferroelectric polarization and electric-field-dependent effective permittivity are obtained in the PbZrO3-0.4SrTiO3 thin film due to the coexistence of rhombohedral (R), tetragonal (T), and orthorhombic (O) polymorphic nanodomains and polar clusters, which results in simultaneously improved recoverable energy storage density (Wrec ∼73.7 J/cm3) and efficiency (η ∼72%). Moreover, excellent temperature stability (the variations of Wrec and η are both less than 5% as temperature increases from 243 to 393 K) and distinguished fatigue endurance (the variations of Wrec and η are both less than 1% after 108 cycles) are realized in a PbZrO3-0.4SrTiO3 thin film. This study provides a feasible alternative method for designing energy storage materials based on antiferroelectrics. [ABSTRACT FROM AUTHOR]

The effect of uniaxial stress on the ferroelectric properties of SrBi[sub 2]Ta[sub 2]O[sub 9] films with different thicknesses (330, 440, and 660 nm) has been investigated. It is found that both the remnant polarization (Pr) and the spontaneous polarization (Ps) decrease with the application of compressive stress, but increase with the application of tensile stress. And the changes of Pr and Ps become larger for thicker films. For the 660 nm film, as the stress changed from -100 MPa (compressive) to +100 MPa (tensile), the Pr increases from -1.8% to +1.8%. Testing voltages in the range of 3-6 V showed no impact on the amplitude of change on the polarization under mechanical stress. Mechanical stress also did not show significant impact on the coercive field. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Decay processes of artificial two-domain structures with various distances in LiNbO3 crystals were carefully investigated using scanning probe microscope. The decay behavior of the composite domains is found closely related to the set domain distance. Detailed analysis indicates that the tip field mostly affects the lateral domain wall motion of the domains in two-domain structures, while the repulsive force of bound charges mainly influences vertical domain wall motion. Thin sample thickness and large domain distance are inferred beneficial for manufacturing small scaled stable domain structures. [ABSTRACT FROM AUTHOR]

The structural, electric, and magnetic properties were investigated in multisusceptible BaAlxFe12−xO19 (x = 0, 1, 2, and 3) ceramics. It is found that the magnetic domain structure changes abruptly with the increase in the Al3+ concentration, which is responsible for the abnormal coercivity enhancement and the distinct initial magnetization behavior. Smaller Al3+ doping increases the off-center displacement of Fe3+ ions at the trigonal bipyramid by introducing compressive strain, which thus enhances the stability of the ferroelectric phase and improves the ferroelectric Curie temperature of BaFe12O19. Moreover, more stable Al3+ ions can increase the resistance of BaFe12O19. The present results highlight the possible application of Al3+ doped BaFe12O19 ceramics as a multisusceptible single-phase material on multifunctional electronic devices. [ABSTRACT FROM AUTHOR]

The complex conductive behavior of ferroelectric domain walls is attracting more and more attention for their potential application as an independent nanoelectronic component. For the (001) epitaxial BiFeO3 films, we find that the domain wall conductivity varies among 71° domain walls, with tail-to-tail (T-T) domain walls more conductive than head-to-head (H-H) and head-to-tail (H-T) ones. Furthermore, it is observed that most of the conductive areas are composed of two parallel lines around the T-T domain walls. These experimental results can be well simulated by our theoretical model based on the polarization configuration and a tunneling mechanism. Our work will help to understand the mechanism of domain wall conductance in ferroelectric materials and further promote the usage of domain walls in advanced nano-devices. [ABSTRACT FROM AUTHOR]

Growth and decay processes of linear domains in lithium niobate single crystals fabricated utilizing scanning probe microscopy were investigated. It is found that the initial configuration of linear domains is dependent on the fabrication parameters as scan velocity and voltage. The linear domains decay at the part where the domain width is small for two different processes. A comparison of critical stable domain size between dot and linear domains was carried out. The critical linear domain width is 0.7 times as large as the critical diameter of dot domain at the same sample thickness due to their smaller surface energy. [ABSTRACT FROM AUTHOR]

A correction to the article "Growth Evolution and Decay Properties of the Abnormally Switched Domains in LinbO3 Crystals" that was published in the January 2009 issue is presented.

When multiferroic terbium manganite (TbMnO3) crystal cylinders are periodically arranged in a square lattice, the resulting two-dimensional (2D) system exhibits photonic band gaps (PBGs). The absolute PBG originating from the Mie resonance is modulated from closed to open by applying an external static magnetic field, which is attributed to the electromagnon depression of the dielectric constant by the rearrangement of antiferromagnetic order. Tunable electromagnetic band structure may be realized by controlling the magnetic transition of manganese spins in TbMnO3. [ABSTRACT FROM AUTHOR]

Polycrystalline Lu3Fe5O12 ceramics with garnet structure were prepared by a solid-state reaction method. A dielectric relaxor behavior at low temperature was observed which may come from the dipolar effects associated with the charge carrier hopping between Fe2+ and Fe3+. It is noticeable that their magnetodielectric (MD) properties are excellent since the applied small magnetic fields can dramatically change the dielectric constants of Lu3Fe5O12 ceramics. The origin of the MD effect is discussed. [ABSTRACT FROM AUTHOR]

A correction is presented regarding the spelling of Xiaomei Lu, one of the author's name associated with the article “Tunable and absolute electromagnetic vacuum in two-dimensional photonic-band-gap Based on multiferroic materials” in the volume 99, 2011 issue of "Applied Physics Letters."