We compare chemical solution deposition (CSD), and pulsed-laser-deposition (PLD), specimens of the new room-temperature, single-phase, multiferroic magnetoelectric, [PbFe2/3W1/3O3]x[PbZr0.53Ti0.47O3]1-x (PZTFWx ~ 0.40<x<0.20) with polarization, loss (<1%), and resistivity (typically 108 ohm.cm) equal to or superior to BiFeO3. Single phase polycrystalline multiferroics PZTFWx thin films were fabricated on platinized silicon substrate by CSD and as epitaxial single-crystal films on MgO substrate by PLD. High dielectric constants (1200- 3000), high polarization (30 - 60 micro C/cm2), weak saturation magnetization (0.48 - 4.53 emu/cm3), a broad dielectric temperature peak, high-frequency dispersion, low dielectric loss and low leakage current were observed in these materials, suggesting the family as candidates for room-temperature multiferroic devices. The ferroelectric switching in these materials can be suppressed or quenched with applied magnetic field.
The review covers the theoretical and experimental results obtained in the recent years by the scientists with the help of comprehensive investigation of nanoferroics and multiferroics. The main attention will be paid to spontaneous flexoeffects and reentrant phase in nanoferroics as well as to a recently discovered giant magnetoelectric effect in multiferroics.
Strain-Induced Relaxor Multiferroicity at Room Temperature in Hexaferrite BaFe12O19 Thin Films
Cornell University（康奈尔大学）；The Pennsylvania State University（宾夕法尼亚州立大学）；Leibniz-Institut für Kristallzüchtung（莱布尼兹晶体生长研究所）；Oak Ridge National Laboratory（橡树岭国家实验室）；University of Tennessee（田纳西大学）；University of California, Berkeley（加州大学伯克利分校）；University of North Texas（北德克萨斯大学）；University of Southern California（南加州大学）；Kavli Institute at Cornell for Nanoscale Science（康奈尔纳米科学卡弗里研究所）
Coexistence of Ferroelectric and Relaxor-like Phases in a Multiferroic Solid Solution (1-x)Pb(Fe$_{1/2}$Nb$_{1/2}$)O$_3$-xPbMnO$_3$
Institute of Physics, National Academy of Sciences of Ukraine（乌克兰国家科学院物理研究所）；Frantsevich Institute for Problems in Materials Science, National Academy of Sciences of Ukraine（乌克兰国家科学院弗兰采维奇材料科学问题研究所）；Ye. O. Paton Institute of Materials Science and Welding, National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”（乌克兰国立技术大学“伊戈尔·西科尔斯基基辅理工学院”叶·奥·帕顿材料科学与焊接研究所）
The fundamental aspects of relaxation dynamics in Bi0.9Gd0.1Fe0.9Mn0.1O3 multiferroic system have been reported. The study was carried out employing dielectric relaxation spectroscopy covering eight decades in frequency 0.01 to106 Hz and in a wide range of temperature 423 K to 153 K, hydrostatic pressure 0.1 MPa to 1765 MPa and aging time 0 s to 80000 s. The temperature dependent dielectric response indicates three relaxations processes in the dynamic window of modulus formalism. Variable range hopping model of small polarons manifests the bulk conduction mechanism. The bulk and grain boundary…
Electrical energy storage systems (EESSs) with high energy density and power density are essential for the effective miniaturization of future electronic devices. Among different EESSs available in the market, dielectric capacitors relying on swift electronic and ionic polarization-based mechanisms to store and deliver energy already demonstrate high power densities. However, different intrinsic and extrinsic contributions to energy dissipations prevent ceramic-based dielectric capacitors from reaching high recoverable energy density levels. Interestingly, relaxor ferroelectric-based dielectri…
The perovskite (1-x)YMnO$_3$-xBiFeO$_3$ binary system is very promising because of its multiferroic end members. Nanocrystalline phases have been recently obtained by mechanosynthesis across the system, and the perovskite structural evolution has been described. Two continuous solid solutions with orthorhombic Pnma and rhombohedral R3c symmetries were found, which coexist within a broad compositional interval of 0.5 < x < 0.9. This might be a polar-nonpolar morphotropic phase boundary region, at which strong phase-change magnetoelectric responses can be expected. A major issue is phase decompo…
