The Experts below are selected from a list of 16308 Experts worldwide ranked by ideXlab platform
J F Scott - One of the best experts on this subject based on the ideXlab platform.
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magnetic switching of ferroelectric domains at room temperature in Multiferroic pztft
2013Co-Authors: Donald M Evans, A Schilling, Ashok Kumar, Dilsom A Sanchez, N Ortega, Miryam Arredondo, R S Katiyar, J M Gregg, J F ScottAbstract:Single-phase magnetoelectric Multiferroics are ferroelectric materials that display some form of magnetism. In addition, magnetic and ferroelectric order parameters are not independent of one another. Thus, the application of either an electric or magnetic field simultaneously alters both the electrical dipole configuration and the magnetic state of the material. The technological possibilities that could arise from magnetoelectric Multiferroics are considerable and a range of functional devices has already been envisioned. Realising these devices, however, requires coupling effects to be significant and to occur at room temperature. Although such characteristics can be created in piezoelectric-magnetostrictive composites, to date they have only been weakly evident in single-phase Multiferroics. Here in a newly discovered room temperature Multiferroic, we demonstrate significant room temperature coupling by monitoring changes in ferroelectric domain patterns induced by magnetic fields. An order of magnitude estimate of the effective coupling coefficient suggests a value of ~1 × 10(-7) sm(-1).
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magnetotransport at domain walls in bifeo 3
2012Co-Authors: C H Yeh, Ying-hao Chu, Lane W Martin, Jan Chi Yang, Guneeta Singhbhalla, C W Liang, Powen Chiu, Gustau Catalan, J F ScottAbstract:Domain walls in Multiferroics can exhibit intriguing behaviors that are significantly different from the bulk of the material. We investigate strong magnetoresistance in domain walls of the model Multiferroic BiFeO3 by probing ordered arrays of 109° domain walls with temperature- and magnetic-field-dependent transport. We observe temperature-dependent variations in the transport mechanism and magnetoresistances as large as 60%. These results suggest that by locally breaking the symmetry of a material, such as at domain walls and structural interfaces, one can induce emergent behavior with properties that deviate significantly from the bulk.
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structurally tailored hexagonal ferroelectricity and multiferroism in epitaxial ybfeo3 thin film heterostructures
2012Co-Authors: Young Kyu Jeong, Seungwoo Song, Hyun M Jang, Hyojin Choi, J F ScottAbstract:Multiferroics have received a great deal of attention because of their fascinating physics of order-parameter cross-couplings and their potential for enabling new device paradigms. Considering the rareness of Multiferroic materials, we have been exploring the possibility of artificially imposing ferroelectricity by structurally tailoring antiferromagnets in thin-film forms. YbFeO3 (YbFO hereafter), a family of centrosymmetric rare-earth orthoferrites, is known to be nonferroelectric (space group Pnma). Here we report that a YbFO thin-film heterostructure fabricated by adopting a hexagonal template surprisingly exhibits nonferroelastic ferroelectricity with the Curie temperature of 470 K. The observed ferroelectricity is further characterized by an extraordinary two-step polarization decay, accompanied by a pronounced magnetocapacitance effect near the lower decay temperature, ∼225 K. According to first-principles calculations, the hexagonal P63/mmc–P63mc–P63cm consecutive transitions are primarily respons...
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symmetries and Multiferroic properties of novel room temperature magnetoelectrics lead iron tantalate lead zirconate titanate pft pzt
2011Co-Authors: Dilsom A Sanchez, J F Scott, Ashok Kumar, N Ortega, R Roquemalherbe, R Polanco, R S KatiyarAbstract:Mixing 60-70% lead zirconate titanate with 40-30% lead iron tantalate produces a single-phase, low-loss, room-temperature Multiferroic with magnetoelectric coupling: (PbZr0.53Ti0.47O3) (1-x)- (PbFe0.5Ta0.5O3)x. The present study combines x-ray scattering, magnetic and polarization hysteresis in both phases, plus a second-order dielectric divergence (to epsilon = 6000 at 475 K for 0.4 PFT; to 4000 at 520 K for 0.3 PFT) for an unambiguous assignment as a C2v-C4v (Pmm2-P4mm) transition. The material exhibits square saturated magnetic hysteresis loops with 0.1 emu/g at 295 K and saturation polarization Pr = 25 μC/cm2, which actually increases (to 40 μC/cm2) in the high-T tetragonal phase, representing an exciting new room temperature oxide Multiferroic to compete with BiFeO3. Additional transitions at high temperatures (cubic at T>1300 K) and low temperatures (rhombohedral or monoclinic at T<250 K) are found. These are the lowest-loss room-temperature Multiferroics known, which is a great advantage for magnet...
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symmetries and Multiferroic properties of novel room temperature magnetoelectrics lead iron tantalate lead zirconate titanate pft pzt
2011Co-Authors: Dilsom A Sanchez, J F Scott, Ashok Kumar, N Ortega, R Roquemalherbe, R Polanco, R S KatiyarAbstract:Mixing 60-70% lead zirconate titanate with 40-30% lead iron tantalate produces a single-phase, low-loss, room-temperature Multiferroic with magnetoelectric coupling: (PbZr0.53Ti0.47O3) (1-x)- (PbFe0.5Ta0.5O3)x. The present study combines x-ray scattering, magnetic and polarization hysteresis in both phases, plus a second-order dielectric divergence (to epsilon = 6000 at 475 K for 0.4 PFT; to 4000 at 520 K for 0.3 PFT) for an unambiguous assignment as a C2v-C4v (Pmm2-P4mm) transition. The material exhibits square saturated magnetic hysteresis loops with 0.1 emu/g at 295 K and saturation polarization Pr = 25 μC/cm2, which actually increases (to 40 μC/cm2) in the high-T tetragonal phase, representing an exciting new room temperature oxide Multiferroic to compete with BiFeO3. Additional transitions at high temperatures (cubic at T>1300 K) and low temperatures (rhombohedral or monoclinic at T<250 K) are found. These are the lowest-loss room-temperature Multiferroics known, which is a great advantage for magnetoelectric devices.
Lane W Martin - One of the best experts on this subject based on the ideXlab platform.
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magnetotransport at domain walls in bifeo 3
2012Co-Authors: C H Yeh, Ying-hao Chu, Lane W Martin, Jan Chi Yang, Guneeta Singhbhalla, C W Liang, Powen Chiu, Gustau Catalan, J F ScottAbstract:Domain walls in Multiferroics can exhibit intriguing behaviors that are significantly different from the bulk of the material. We investigate strong magnetoresistance in domain walls of the model Multiferroic BiFeO3 by probing ordered arrays of 109° domain walls with temperature- and magnetic-field-dependent transport. We observe temperature-dependent variations in the transport mechanism and magnetoresistances as large as 60%. These results suggest that by locally breaking the symmetry of a material, such as at domain walls and structural interfaces, one can induce emergent behavior with properties that deviate significantly from the bulk.
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electric field control of local ferromagnetism using a magnetoelectric Multiferroic
2008Co-Authors: Lane W Martin, Marcin Gajek, Chan Ho Yang, Nina Balke, Qing He, Wei Hu, Mikel Holcomb, Qian ZhanAbstract:Multiferroics are of interest for memory and logic device applications, as the coupling between ferroelectric and magnetic properties enables the dynamic interaction between these order parameters. Here, we report an approach to control and switch local ferromagnetism with an electric field using Multiferroics. We use two types of electromagnetic coupling phenomenon that are manifested in heterostructures consisting of a ferromagnet in intimate contact with the Multiferroic BiFeO3. The first is an internal, magnetoelectric coupling between antiferromagnetism and ferroelectricity in the BiFeO3 film that leads to electric-field control of the antiferromagnetic order. The second is based on exchange interactions at the interface between a ferromagnet (Co0.9Fe0.1) and the antiferromagnet. We have discovered a one-to-one mapping of the ferroelectric and ferromagnetic domains, mediated by the colinear coupling between the magnetization in the ferromagnet and the projection of the antiferromagnetic order in the Multiferroic. Our preliminary experiments reveal the possibility to locally control ferromagnetism with an electric field. Multiferroic materials are of interest because they allow control of their magnetic properties through electric fields. However, room-temperature magnetoelectrics often show antiferromagnetic order, reducing the effects of such coupling. A novel approach demonstrates switchable electric field control over a local magnetic field through the indirect route of exchange bias.
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Electric-field control of local ferromagnetism using a magnetoelectric Multiferroic
2008Co-Authors: Ying-hao Chu, Mikel B. Holcomb, Donkoun Lee, Shu-jen Han, Lane W Martin, Marcin Gajek, Chan Ho Yang, Nina Balke, Qing He, Wei HuAbstract:Multiferroics are of interest for memory and logic device applications, as the coupling between ferroelectric and magnetic properties enables the dynamic interaction between these order parameters. Here, we report an approach to control and switch local ferromagnetism with an electric field using Multiferroics. We use two types of electromagnetic coupling phenomenon that are manifested in heterostructures consisting of a ferromagnet in intimate contact with the Multiferroic BiFeO(3). The first is an internal, magnetoelectric coupling between antiferromagnetism and ferroelectricity in the BiFeO(3) film that leads to electric-field control of the antiferromagnetic order. The second is based on exchange interactions at the interface between a ferromagnet (Co(0.9)Fe(0.1)) and the antiferromagnet. We have discovered a one-to-one mapping of the ferroelectric and ferromagnetic domains, mediated by the colinear coupling between the magnetization in the ferromagnet and the projection of the antiferromagnetic order in the Multiferroic. Our preliminary experiments reveal the possibility to locally control ferromagnetism with an electric field.
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controlling magnetism with Multiferroics
2007Co-Authors: Ying-hao Chu, Lane W Martin, Mikel Holcomb, R RameshAbstract:Multiferroics, materials combining multiple order parameters, offer an exciting way of coupling phenomena such as electronic and magnetic order. Using epitaxial growth and heteroepitaxy, researchers have grown high-quality thin films and heterostructures of the Multiferroic BiFeO 3 . The ferroelectric and antiferromagnetic domain structure and coupling between these two order parameters in BiFeO 3 is now being studied. We describe the evolution of our understanding of the connection between structure, properties, and new functionalities (including electrical control of magnetism) using BiFeO 3 as a model system.
R Ramesh - One of the best experts on this subject based on the ideXlab platform.
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discovery of ordered vortex phase in Multiferroic oxide superlattices
2018Co-Authors: Antonio B Mei, R Ramesh, Darrell G SchlomAbstract:Ferroics, characterized by a broken symmetry state with nonzero elastic, polar, or magnetic order parameters $\vec{u}$, are recognized platforms for staging and manipulating topologically-protected structures as well as for detecting unconventional topological phenomena. The unrealized possibility of producing ordered topological phases in magnetoelectric Multiferroics, exhibiting coupled magnetic and polar order parameters, is anticipated to engender novel functionality and open avenues for manipulating topological features. Here, we report the discovery of an ordered $\pi_1$-$S_\infty$ vortex phase within single-phase magnetoelectric Multiferroic BiFeO$_3$. The phase, characterized by positive topological charge and chiral staggering, is realized in coherent TbScO$_3$ and BiFeO$_3$ superlattices and established via the combination of direct- and Fourier-space analyses. Observed order-parameter morphologies are reproduced with a field model describing the local order-parameter stiffness and competing non-local dipole-dipole interactions. Anisotropies canting the order parameter towards $\left $ suppress chiral staggering and produced a competing $\pi_1$-$C_{\infty v}$ vortex phase in which cores are centered.
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deterministic control of ferroelastic switching in Multiferroic materials
2009Co-Authors: Nina Balke, Long-qing Chen, R Ramesh, S Choudhury, Stephen Jesse, Mark Huijben, Arthur P Baddorf, Sergei V KalininAbstract:Multiferroic materials showing coupled electric, magnetic and elastic orderings provide a platform to explore complexity and new paradigms for memory and logic devices. Until now, the deterministic control of non-ferroelectric order parameters in Multiferroics has been elusive. Here, we demonstrate deterministic ferroelastic switching in rhombohedral BiFeO3 by domain nucleation with a scanning probe. We are able to select among final states that have the same electrostatic energy, but differ dramatically in elastic or magnetic order, by applying voltage to the probe while it is in lateral motion. We also demonstrate the controlled creation of a ferrotoroidal order parameter. The ability to control local elastic, magnetic and torroidal order parameters with an electric field will make it possible to probe local strain and magnetic ordering, and engineer various magnetoelectric, domain-wall-based and strain-coupled devices.
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strain control of domain wall stability in epitaxial bifeo3 110 films
2007Co-Authors: Ying-hao Chu, Long-qing Chen, M P Cruz, J X Zhang, P L Yang, F Zavaliche, Padraic Shafer, R RameshAbstract:Multiferroics, or materials that simultaneously show magnetic and ferroelectric order, hold the promise of coupling between magnetic and electric order parameters [1‐ 3]. While the phenomenon is by itself of fundamental importance, the possibility for control of magnetic properties with an electric field (and vice versa) is of significant interest for applications in high frequency devices, storage media, and electric field control of spintronics. The cross correlation between magnetic and electric domains has been observed by optical techniques in one model Multiferroic, YMnO 3 [2]. The stability of switched (written) domains against time is one of the critical issues for applications of Multiferroics. It is well understood that favorable domain-wall configurations correspond to those having low wall energy that satisfies the electrical, magnetic, and mechanical compatibility conditions. A basic understanding of the distributions of electric, magnetic, and stress fields within domain structures allows one to manipulate the relative stability of domains and domain walls. This work explores the effect of substrate-film mismatch strain on internal stress distributions within domain structures and thus the domain stability and domain-wall motion in Multiferroic BiFeO3 (BFO) thin films. Such an approach is rather general and can be employed to control the stability of other ferroic systems [4,5].
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controlling magnetism with Multiferroics
2007Co-Authors: Ying-hao Chu, Lane W Martin, Mikel Holcomb, R RameshAbstract:Multiferroics, materials combining multiple order parameters, offer an exciting way of coupling phenomena such as electronic and magnetic order. Using epitaxial growth and heteroepitaxy, researchers have grown high-quality thin films and heterostructures of the Multiferroic BiFeO 3 . The ferroelectric and antiferromagnetic domain structure and coupling between these two order parameters in BiFeO 3 is now being studied. We describe the evolution of our understanding of the connection between structure, properties, and new functionalities (including electrical control of magnetism) using BiFeO 3 as a model system.
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Multiferroics progress and prospects in thin films
2007Co-Authors: R Ramesh, Nicola A. SpaldinAbstract:Multiferroic materials, which show simultaneous ferroelectric and magnetic ordering, exhibit unusual physical properties — and in turn promise new device applications — as a result of the coupling between their dual order parameters. We review recent progress in the growth, characterization and understanding of thin-film Multiferroics. The availability of high-quality thin-film Multiferroics makes it easier to tailor their properties through epitaxial strain, atomic-level engineering of chemistry and interfacial coupling, and is a prerequisite for their incorporation into practical devices. We discuss novel device paradigms based on magnetoelectric coupling, and outline the key scientific challenges in the field.
Shuai Dong - One of the best experts on this subject based on the ideXlab platform.
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realization of large electric polarization and strong magnetoelectric coupling in bimn3cr4o12
2017Co-Authors: Long Zhou, Shuai Dong, Yisheng Chai, Jianhong Dai, Huimin Zhang, Huibo Cao, S Calder, Yunyu Yin, Xiao Wang, Xudong ShenAbstract:Magnetoelectric Multiferroics have received much attention in the past decade due to their interesting physics and promising multifunctional performance. For practical applications, simultaneous large ferroelectric polarization and strong magnetoelectric coupling are preferred. However, these two properties have not been found to be compatible in the single-phase Multiferroic materials discovered as yet. Here, it is shown that superior Multiferroic properties exist in the A-site ordered perovskite BiMn3 Cr4 O12 synthesized under high-pressure and high-temperature conditions. The compound experiences a ferroelectric phase transition ascribed to the 6s2 lone-pair effects of Bi3+ at around 135 K, and a long-range antiferromagnetic order related to the Cr3+ spins around 125 K, leading to the presence of a type-I Multiferroic phase with huge electric polarization. On further cooling to 48 K, a type-II Multiferroic phase induced by the special spin structure composed of both Mn- and Cr-sublattices emerges, accompanied by considerable magnetoelectric coupling. BiMn3 Cr4 O12 thus provides a rare example of joint Multiferroicity, where two different types of Multiferroic phases develop subsequently so that both large polarization and significant magnetoelectric effect are achieved in a single-phase Multiferroic material.
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Multiferroic materials and magnetoelectric physics symmetry entanglement excitation and topology
2015Co-Authors: Shuai Dong, Sangwook Cheong, Junming Liu, Zhifeng RenAbstract:Multiferroics are those materials with more than one ferroic order, and magnetoelectricity refers to the mutual coupling between magnetism and electricity. The discipline of Multiferroicity has never been so highly active as that in the first decade of the twenty-first century, and it has become one of the hottest disciplines of condensed matter physics and materials science. A series of milestones and steady progress in the past decade have enabled our understanding of Multiferroic physics substantially comprehensive and profound, which is further pushing forward the research frontier of this exciting area. The availability of more Multiferroic materials and improved magnetoelectric performance are approaching to make the applications within reach. While seminal review articles covering the major progress before 2010 are available, an updated review addressing the new achievements since that time becomes imperative. In this review, following a concise outline of the basic knowledge of Multiferroicity and magnetoelectricity, we summarize the important research activities on Multiferroics, especially magnetoelectricity and related physics in the last six years. We consider not only single-phase Multiferroics but also Multiferroic heterostructures. We address the physical mechanisms regarding magnetoelectric coupling so that the backbone of this divergent discipline can be highlighted. A series of issues on lattice symmetry, magnetic ordering, ferroelectricity generation, electromagnon excitations, Multiferroic domain structure and domain wall dynamics, and interfacial coupling in Multiferroic heterostructures, will be revisited in an updated framework of physics. In addition, several emergent phenomena and related physics, including magnetic skyrmions and generic topological structures associated with magnetoelectricity will be discussed.
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Multiferroic materials and magnetoelectric physics symmetry entanglement excitation and topology
2015Co-Authors: Shuai Dong, Sangwook CheongAbstract:Multiferroics are those materials with more than one ferroic order, and magnetoelectricity refers to the mutual coupling between magnetism (spins and/or magnetic field) and electricity (electric dipoles and/or electric field). In spite of the long research history in the whole twentieth century, the discipline of Multiferroicity has never been so highly active as that in the first decade of the twenty-first century, and it has become one of the hottest disciplines of condensed matter physics and materials science. A series of milestones and steady progress in the past decade have enabled our understanding of Multiferroic physics substantially comprehensive and profound, which is further pushing forward the research frontier of this exciting area. The availability of more Multiferroic materials and improved magnetoelectric performance are approaching to make the applications within reach. While seminal review articles covering the major progress before 2010 are available, an updated review addressing the n...
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RECENT PROGRESS OF Multiferroic PEROVSKITE MANGANITES
2012Co-Authors: Shuai Dong, Junming LiuAbstract:So far tens of Multiferroic materials, with various chemical compositions and crystal structures, have been discovered in the past years. Among these Multiferroics, some perovskite manganites with ferroelectricity driven by magnetic orders are of particular interest. In these Multiferroic perovskite manganites, the Multiferroic phenomena are not only quite prominent, but the involved physical mechanisms are also very plenty and representative. In this brief review, we will introduce some recent theoretical and experimental progress on Multiferroic manganites, including the fascinating microscopic physics and very recently addressed experimental findings with attractive Multiferroicity.
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recent progress of Multiferroic perovskite manganites
2012Co-Authors: Shuai Dong, Junming LiuAbstract:Many Multiferroic materials, with various chemical compositions and crystal structures, have been discovered in the past years. Among these Multiferroics, some perovskite manganites with ferroelectricity driven by magnetic orders are of particular interest. In these Multiferroic perovskite manganites, not only their Multiferroic properties are quite prominent, but also the involved physical mechanisms are very plenty and representative. In this Brief Review, we will introduce some recent theoretical and experimental progress on Multiferroic manganites.
Young Sun - One of the best experts on this subject based on the ideXlab platform.
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giant magnetoelectric effects achieved by tuning spin cone symmetry in y type hexaferrites
2017Co-Authors: Kun Zhai, Li-qin Yan, Yisheng Chai, Huibo Cao, Shipeng Shen, Wei Tian, B C Chakoumakos, Dashan Shang, Fangwei Wang, Young SunAbstract:Multiferroics materials, which exhibit coupled magnetic and ferroelectric properties, have attracted tremendous research interest because of their potential in constructing next-generation multifunctional devices. The application of single-phase Multiferroics is currently limited by their usually small magnetoelectric effects. Here, we report the realization of giant magnetoelectric effects in a Y-type hexaferrite Ba0.4Sr1.6Mg2Fe12O22 single crystal, which exhibits record-breaking direct and converse magnetoelectric coefficients and a large electric-field-reversed magnetization. We have uncovered the origin of the giant magnetoelectric effects by a systematic study in the Ba2-x Sr x Mg2Fe12O22 family with magnetization, ferroelectricity and neutron diffraction measurements. With the transverse spin cone symmetry restricted to be two-fold, the one-step sharp magnetization reversal is realized and giant magnetoelectric coefficients are achieved. Our study reveals that tuning magnetic symmetry is an effective route to enhance the magnetoelectric effects also in Multiferroic hexaferrites. Control of the electrical properties of materials by means of magnetic fields or vice versa may facilitate next-generation spintronic devices, but is still limited by their intrinsically weak magnetoelectric effect. Here, the authors report the existence of an enhanced magnetoelectric effect in a Y-type hexaferrite, and reveal its underlining mechanism.
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cross coupling between electric and magnetic orders in a Multiferroic metal organic framework
2015Co-Authors: Ying Tian, Li-qin Yan, Alessandro Stroppa, Yisheng Chai, Shouguo Wang, Paolo Barone, Silvia Picozzi, Young SunAbstract:The coexistence of both electric and magnetic orders in some metal-organic frameworks (MOFs) has yielded a new class of Multiferroics beyond inorganic materials. However, the coupling between two orders in Multiferroic MOFs has not been convincingly verified yet. Here we present clear experimental evidences of cross coupling between electric and magnetic orders in a Multiferroic MOF [(CH3)2NH2]Fe(HCOO)3 with a perovskite structure. The dielelectric constant exhibit a hump just at the magnetic ordering temperature TN. Moreover, both the direct (magnetic field control of dielectric properties) and converse (electric field control of magnetization) magnetoelectric effects have been observed in the Multiferroic state. This work opens up new insights on the origin of ferroelectricity in MOFs and highlights their promise as magnetoelectric Multiferroics.
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low magnetic field reversal of electric polarization in a y type hexaferrite
2011Co-Authors: Fen Wang, Li-qin Yan, Tao Zou, Yi Liu, Young SunAbstract:Magnetoelectric Multiferroics in which ferroelectricity and magnetism coexist have attracted extensive attention because they provide great opportunities for the mutual control of electric polarization by magnetic fields and magnetization by electric fields. From a practical point view, the main challenge in this field is to find proper Multiferroic materials with a high operating temperature and great magnetoelectric sensitivity. Here we report on the magnetically tunable ferroelectricity and the giant magnetoelectric sensitivity up to 250 K in a Y-type hexaferrite, BaSrCoZnFe11AlO22. Not only the magnitude but also the sign of electric polarization can be effectively controlled by applying low magnetic fields (a few hundreds of Oe) that modifies the spiral magnetic structures. The magnetically induced ferroelectricity is stabilized even in zero magnetic field. Decayless reproducible flipping of electric polarization by oscillating low magnetic fields is shown. The maximum linear magnetoelectric coefficient reaches a high value of ~ 3.0\times10^3 ps/m at 200 K.
