Multiferroic Research Articles

Cutting-edge technologies and recent modernization on multifunctional perovskite materials for green energy conversion and spintronic applications

Cutting-edge technologies and recent modernization on multifunctional perovskite materials for green energy conversion and spintronic applications

Non-volatile voltage-controlled magnetization in single-phase multiferroic ceramics at room temperature

Non-volatile voltage-controlled magnetization in single-phase multiferroic ceramics at room temperature

Theoretical Justification of Structural, Magnetoelectronic and Optical Properties in QFeO3 (Q = Bi, P, Sb): A First-Principles Study.

One of the primary objectives of scientific research is to create state-of-the-art multiferroic (MF) materials that exhibit interconnected properties, such as piezoelectricity, magnetoelectricity, and magnetostriction, and remain functional under normal ambient temperature conditions. In this study, we employed first-principles calculations to investigate how changing pnictogen elements affect the structural, electronic, magnetic, and optical characteristics of QFeO3 (Q = Bi, P, SB). Electronic band structures reveal that BiFeO3 is a semiconductor compound; however, PFeO3 and SbFeO3 are metallic. The studied compounds are promising for spintronics, as they exhibit excellent magnetic properties. The calculated magnetic moments decreased as we replaced Bi with SB and P in BiFeO3. A red shift in the values of ε2(ω) was evident from the presented spectra as we substituted Bi with Sb and P in BiFeO3. QFeO3 (Q = Bi, P, SB) showed the maximum absorption of incident photons in the visible region. The results obtained from calculating the optical parameters suggest that these materials have a strong potential to be used in photovoltaic applications.

First Observation of Induced Ferroelectric and Magnetoelectric Properties in Pristine and Ni‐Intercalated Mo2TiC2Tx Double Transition Metal MXene

AbstractIn recent years, multiferroic (MF) materials have attained remarkable attention because of their exceptional ability to demonstrate both ferroelectric (FE) and magnetic properties simultaneously which has lead to their applications in memory, sensors, and energy storage devices. Here, a simple synthesis approach is used to enhance the ferroelectricity and induce the multiferroicity in double transition metal carbide (DTM) MXene film. The successful synthesis is confirmed by X‐ray Diffraction (XRD), Raman Spectroscopy, and Scanning Electron Microscopy (SEM) analysis. In addition, the FE and magnetic hysteresis (MH) loops are conducted to observe the nature of synthesized materials. Furthermore, the magnetoelectric (ME) effect is also examined to explore its significance in data storage and ME signal generation devices. Thus, the findings reveal the first report on the co‐existence of FE and magnetic properties of DTM MXene for potential applications in nano‐electronic devices of future technology.

Modelling the effect of particle arrangement on the magnetoelectric response of a polymer multiferroic film.

In this work the behavior of a three-component composite multiferroic (MF)-an electrically neutral polymer matrix filled with a mixture of piezoelectric and ferromagnetic micrometer-size particles-is investigated in the framework of a simple mesoscopic model. The main issue of interest is the electric polarization generated in a thin film of such an MF in response to a quasistatic magnetic field. The driving mechanism of the effect is rotation of magnetically hard particles inside the matrix which, in turn, transfers the arisen mechanical stresses to the piezoelectric grains. The model MF film is constructed as a periodic set of 2D cells each of which contains one piezoelectric and two ferromagnetic particles. The numerical simulations are performed by means of finite element method on a single cell which, however, is incorporated in an infinite film by means of periodic boundary conditions. The problem of how the spatial arrangement of the particles and the orientation of the anisotropy axis of the piezoelectric one affect the magnetoelectric response is discussed.

Axion-matter coupling in multiferroics

Multiferroics (MFs) are materials with two or more ferroic orders, like spontaneous ferroelectric and ferromagnetic polarizations. Such materials can exhibit a magnetoelectric effect whereby magnetic and ferroelectric polarizations couple linearly, reminiscent of, but not identical to the electromagnetic $\mathbit{E}\ifmmode\cdot\else\textperiodcentered\fi{}\mathbit{B}$ axion coupling. Here we point out a possible mechanism in which an external dark matter axion field couples linearly to ferroic orders in these materials without external applied fields. We find the magnetic response to be linear in the axion-electron coupling. At temperatures close to the ferromagnetic transition fluctuations can lead to an enhancement of the axion-induced magnetic response. Relevant material candidates such as the Lu-Sc hexaferrite family are discussed.

Potential room-temperature multiferroicity in cupric oxide under high pressure

CuO, known to be multiferroic (MF) from ${T}_{L}\phantom{\rule{4pt}{0ex}}=\phantom{\rule{4pt}{0ex}}213\phantom{\rule{4pt}{0ex}}\mathrm{K}$ to ${T}_{N}\phantom{\rule{4pt}{0ex}}=\phantom{\rule{4pt}{0ex}}230\phantom{\rule{4pt}{0ex}}\mathrm{K}$ at ambient pressure, has been the subject of debates about its ability to exhibit multiferroicity at room temperature (RT) under high hydrostatic pressure. Here we address this question based on theoretical and experimental investigations. The influence of hydrostatic pressure on ${T}_{L}$ and ${T}_{N}$ has been estimated from ab initio calculations combined with classical Monte-Carlo simulations and a quasi-1D antiferromagnetic analytical model. From the experimental side, electric permittivity anomalies related to ferroelectric transitions have been followed with dielectric measurements on single crystals up to 6.1 GPa. We show that the temperature ${T}_{N}$ below which the MF state forms increases with pressure linearly to higher pressure that hitherto supposed, and indeed based on our calculations, should exceed RT above about 20 GPa.

An effective strategy for the development of multiferroic composite nanostructures with enhanced magnetoelectric coupling performance: a perovskite-spinel approach.

An energy efficient move toward the regulation of magnetization vector solely with E-field by developing multiferroic (MF) magnetoelectric (ME) nanostructures' have opened up vast avenues for novel low power consumption memories and magnetoelectric devices. The present study delineates the development of multiferroic nanocomposites (MF NCs) with perovskite BiFeO3 and spinel NiFe2O4. A simple Pechini one-pot method is employed for the preparation of nanocomposites with different molar concentrations and the modified structural, magnetic, dielectric, and magnetoelectric performance of NCs is carried out at room temperature. The purity in the crystalline phase of BiFeO3 and NiFe2O4 in the NCs are corroborated by XRD and FTIR spectroscopy, which is further substantiated, while EDAX analysis pointed out the elemental composition. The SEM images provide an evidence for the closely compacted and agglomerated grains with some voids in the prepared sample. A well saturated magnetic hysteresis (M–H) loop reveals long range ferromagnetic ordering and the remanence value ascertains the multidomain structure. The dielectric performance and impedance analysis imparts greater knowledge of the dependence of grain and grain boundaries on the resistive and conductive behavior of the composites. The frequency dependence of electric modulus and impedance exhibits a non-Debye type of relaxation process. The P–E hysteresis loops clearly show the lossy behavior of the composites with an increase in the NiFe2O4 concentration. The ME coupling coefficient of the composites evaluated using the dynamic magnetic field method demonstrates the effective coupling interaction between ferroelectric (FE) perovskite BiFeO3 and ferromagnetic (FM) spinel NiFe2O4. Thus, the findings disclose a greater potential for innovative applications in spintronics and information technology.

Multiferroics: Looking back and going forward

Multiferroics: Looking back and going forward

Magnetoelectric Composites: Applications, Coupling Mechanisms, and Future Directions

Multiferroic (MF)-magnetoelectric (ME) composites, which integrate magnetic and ferroelectric materials, exhibit a higher operational temperature (above room temperature) and superior (several orders of magnitude) ME coupling when compared to single-phase multiferroic materials. Room temperature control and the switching of magnetic properties via an electric field and electrical properties by a magnetic field has motivated research towards the goal of realizing ultralow power and multifunctional nano (micro) electronic devices. Here, some of the leading applications for magnetoelectric composites are reviewed, and the mechanisms and nature of ME coupling in artificial composite systems are discussed. Ways to enhance the ME coupling and other physical properties are also demonstrated. Finally, emphasis is given to the important open questions and future directions in this field, where new breakthroughs could have a significant impact in transforming scientific discoveries to practical device applications, which can be well-controlled both magnetically and electrically.

Progress in multiferroic and magnetoelectric materials: applications, opportunities and challenges

The development of electronic technology is flexibly related to the progresses made in material science. Functional materials out of the broad class of materials available today offer unique chance for developing novel components and devices. In this framework, provides a new class of functional materials, the multiferroics (MFs), combine two or more different ferroic orders (viz. ferroelectric, ferromagnetic and ferroelastic) in a single phase and are utilized in a broad range of systems. In connection with multiferroism, a broad category of materials namely magnetoelectrics allow the electric control on magnetization or vice-versa are explored extensively. Even though, the research in the field of MFs and magnetoelectric (ME) materials can be traced back to revolutionary research in the early 1950s. There has been a contemporary resurgence of concern motivation by long-term technological aspirations. The center of attention of this review is on elementary understanding of the MFs and ME materials using a multidisciplinary approach to address the underlying mechanism responsible for the coupling, their applications in some novel devices, new opportunities and future challenges.

Synthesis and Characterization of BSLT–NZFO Multiferroic Composite

Synthesis and Characterization of BSLT–NZFO Multiferroic Composite

Ce-doping effect on modulation of spin-exchange interaction and dielectric behaviour of nanostructured LaFeO3 orthoferrites

Abstract In present attempt, Ce-doped LaFeO3 (LCFO) system is explored as single phase room temperature multiferroics (MFs). Nano-crystalline LCFO system with various compositions of Ce [La1-xCexFeO3 (0 ≤ x ≤ 0.1)] are synthesized by microwave-assisted gel combustion method. Detailed Rietveld analysis of X-ray diffraction data revealed that the systems retain distorted orthorhombic phase with space group Pbmn for x

Research on Multiferroics by Using Mössbauer Spectroscopy

Research on Multiferroics by Using Mössbauer Spectroscopy

Modeling of multilevel cell memory with theBaTiO3/Fenanostructured multiferroic composite material

In order to enhance the performance of calculators, multilevel cell (MLC) memories have been proposed as an alternative solution to improve the communication speed between their processors and memories, and also in order to increase the effective storage density of memory devices. In this Rapid Communication, we propose a model of MLC memory based on a multiferroic (MF) composite material. We introduce a one-dimensional trilayer ferromagnetic/ferroelectric/ferromagnetic MF composite material through which we investigate theoretically the dynamics of an electromagnon excitation displaying a soliton structure with an envelope shape. It emerges from this study based on barium titanate (${\text{BaTiO}}_{3}$) and iron (Fe) that, for suitable values of the parameters of a single initial polarization excitation, some propagation scenarios display the encoding of the states of a system of two magnetic bits, i.e., the 11, 10, 01, and 00 states. In addition to this result, it is also realized that the system exhibits another scenario for which the signal propagating in the MF material is alternately converted from an electrical signal into a magnetic signal and reversely. Such outcomes suggest, on the one hand, the possibility to model a four-level MLC memory, and on the other hand, the modeling of an electromagnetic oscillator, based on a MF composite material.

Anomalous freezing of dielectric polarons near magnetic ordering in multiferroic La0.5Bi0.5FeO3

Abstract A single-phase multiferroic (MF) La0.5Bi0.5FeO3 (LBFO) ceramic sample was prepared by the conventional solid-state reaction method. The crystallographic phase formation and morphological studies were carried out using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The temperature-dependent magnetization exhibits weak ferromagnetic ordering near TC = 220 K. Complex dielectric and impedance properties of LBFO as a function of temperature and frequency were performed to understand the correlation between magnetic and dielectric properties. The analysis of electrical modulus spectrum reveals that the magnetic ordering imposes a change in the activation energy of dielectric polarons. The thermal fluctuations of magnetic moments activate the freezing of dielectric polarons with enhancement in temperature.

Structural, Electronic, and Magnetic Analysis and Device Characterization of Ferroelectric–Ferromagnetic Heterostructure (BZT–BCT/LSMO/LAO) Devices for Multiferroic Applications

Ferroelectricity and ferromagnetism have been investigated in a lead-free 0.5Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Ca0.3)TiO3 (BZT–BCT)/La0.7Sr0.3MnO3 (LSMO) heterostructure for multiferroic (MF) applications. The BZT–BCT thin film has been grown on LSMO/lanthanum aluminate, LaAlO3 (LAO) by pulsed laser deposition (PLD). Prior to that, the LSMO layer was deposited on a single-crystal LAO substrate by PLD. The epitaxial growth of the (001) oriented films was confirmed by X-ray diffraction analysis. The small value of the full-width at half-maximum of the rocking curve peak (0.1°) performed about (002) plane of the BZT–BCT film indicates an out-of-plane orientation of the film. The polarization switching behavior in the heterostructure device was observed with a remnant polarization of $\sim 47~\boldsymbol {\mu \text {C}/}{{\text {cm}}}^{2}$ and a coercive field of ~180kV/cm at an applied voltage of 5 V. The frequency-dependent relative dielectric constant varies in-between 5100 and 4900 in the frequency range from 1 to 50 kHz during the dielectric measurements of the fabricated device. The observed low value of the dielectric loss (0.02) confirms the outstanding quality of the ferroelectric device. A well-saturated room temperature magnetization–applied field curve, with a coercive field of ~1200A/m and a remnant magnetization of ~110kA/m, was observed in the LSMO/LAO system indicating the ferromagnetic behavior of the film. The temperature-dependent magnetization of the LSMO film exhibits a ferromagnetic-to-paramagnetic transition at ~360K. These results on all solid-state ferroelectric–ferromagnetic heterostructure using BZT–BCT and LSMO open viable possibilities for MF applications.

Voltage control of unidirectional anisotropy in ferromagnet-multiferroic system.

Demonstration of ultralow energy switching mechanisms is imperative for continued improvements in computing devices. Ferroelectric (FE) and multiferroic (MF) order and their manipulation promise an ideal combination of state variables to reach attojoule range for logic and memory (i.e., ~30× lower switching energy than nanoelectronics). In BiFeO3 (BFO), the coupling between the antiferromagnetic (AFM) and FE order is robust at room temperature, scalable in voltage, stabilized by the FE order, and can be integrated into a fabrication process for a beyond-CMOS (complementary metal-oxide semiconductor) era. The presence of the AFM order and a canted magnetic moment in this system causes exchange interaction with a ferromagnet such as Co0.9Fe0.1 or La0.7Sr0.3MnO3. Previous research has shown that exchange coupling (uniaxial anisotropy) can be controlled with an electric field. However, voltage modulation of unidirectional anisotropy, which is preferred for logic and memory technologies, has not yet been demonstrated. Here, we present evidence for electric field control of exchange bias of laterally scaled spin valves that is exchange coupled to BFO at room temperature. We show that the exchange bias in this bilayer is robust, electrically controlled, and reversible. We anticipate that magnetoelectricity at these scaled dimensions provides a powerful pathway for computing beyond modern nanoelectronics by enabling a new class of nonvolatile, ultralow energy computing elements.

Effects of La doping on structural, magnetic, and ferroelectric properties of Aurivillius Bi6Fe1.4Co0.6Ti3O18 thin films

The effects of La ions substitution on the structural, magnetic, ferroelectric and leakage properties of Aurivillius Bi6−xLaxFe1.4Co0.6Ti3O18 (BLFCTO, 0 ≤ x ≤ 1) thin films are investigated. X-ray diffraction (XRD) refinement results indicate that all the samples have an orthorhombic crystal structure and the space group of B2cb. The coexistence of room-temperature ferromagnetism and ferroelectricity can be found in all the samples. Doping La ions can increase ferroelectricity magnitude and decrease leakage current. Furthermore, the energy conversion efficiency can be significantly improved from 16.0 to 53.1% due to the decrease of leakage current. The remanent magnetization 2Mr of 8.2 emu/cm3 and polarization 2Pr of 37.4 µC/cm2 are observed in the x = 0.6 sample. The changes of magnetic, ferroelectric, and leakage properties are discussed in terms of lattice distortion, grain size, oxygen vacancy and compactness. The present work provides an available way to explore room-temperature multiferroics (MFs) and optimize energy efficiency in Aurivillius compounds.

The Magnetic and Electric Measurements of the Multiferroic PbFe1/2Nb1/2O3 Ceramics Obtained Using Hot Uniaxial Pressure Method

The Magnetic and Electric Measurements of the Multiferroic PbFe1/2Nb1/2O3 Ceramics Obtained Using Hot Uniaxial Pressure Method