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Статті в журналах з теми "Multiferroic Oxides - Structural Properties"

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Автор: Grafiati

Опубліковано: 7 вересня 2023

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1

Gareeva Z. V., Zvezdin A. K., Shulga N. V., Gareev T. T., and Chen X. M. "Mechanisms of magnetoelectric effects in oxide multiferroics with a perovskite praphase." Physics of the Solid State 64, no. 9 (2022): 1324. http://dx.doi.org/10.21883/pss.2022.09.54175.43hh.

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Анотація:

Magnetoelectric effects are discussed in multiferroics with the perovskite structure: bismuth ferrite, rare-earth orthochromites, and Ruddlesden--Popper structures belonging to the trigonal, orthorhombic, and tetragonal syngonies. The influence of structural distortions on magnetic and ferroelectric properties is studied, possible magnetoelectric effects (linear, quadratic, inhomogeneous) in these materials are determined, and expressions for the linear magnetoelectric effect tensor are given. Macroscopic manifestations of the inhomogeneous magnetoelectric effect in multiferroic nanoelements are considered. Keywords: multiferroics, magnetoelectric effect, perovskites, symmetry.

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2

Xu, Xiaoshan, and Wenbin Wang. "Multiferroic hexagonal ferrites (h-RFeO3, R = Y, Dy-Lu): a brief experimental review." Modern Physics Letters B 28, no. 21 (August 20, 2014): 1430008. http://dx.doi.org/10.1142/s0217984914300087.

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Hexagonal ferrites ( h - RFeO 3, R = Y , Dy - Lu ) have recently been identified as a new family of multiferroic complex oxides. The coexisting spontaneous electric and magnetic polarizations make h - RFeO 3 rare-case ferroelectric ferromagnets at low temperature. Plus the room-temperature multiferroicity and the predicted magnetoelectric effect, h - RFeO 3 are promising materials for multiferroic applications. Here we review the structural, ferroelectric, magnetic and magnetoelectric properties of h - RFeO 3. The thin film growth is also discussed because it is critical in making high quality single crystalline materials for studying intrinsic properties.

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3

Lorenz, Michael. "Pulsed laser deposition of functional oxides - towards a transparent electronics." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1412. http://dx.doi.org/10.1107/s2053273314085878.

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Metal oxides, in particular with transition metals, show strong electronic correlations which determine a huge variety of electronic properties, together with other functionalities. For example, ZnO and Ga2O3 as wide-bandgap semiconductors have a high application potential as transparent functional layers in future oxide electronics [1-2]. Other oxides of current interest are ferrimagnetic spinels of the type MFe2O4 (M=Zn,Co,Ni), see K. Brachwitz et al. Appl. Phys. Lett. 102, 172104 (2013), or highly correlated iridate films, see M. Jenderka et al. Phys. Rev. B 88, 045111 (2013). Furthermore, combinations of ferroelectric and magnetic oxides in multiferroic composites and multilayers show promising magnetoelectric coupling. For the exploratory growth of the above mentioned novel oxides into nm-thin films, pulsed laser deposition (PLD) appears as the method of choice because of its extremely high flexibility in terms of material and growth conditions, high growth rate and excellent structural properties [3]. This talk highlights recent developments of new functional oxides using unique large-area PLD processes running for more than two decades in the lab of the author [3].

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4

Watson, Carla, Tara Peña, Marah Abdin, Tasneem Khan, and Stephen M. Wu. "Dynamic adhesion of 2D materials to mixed-phase BiFeO₃ structural phase transitions." Journal of Applied Physics 132, no. 4 (July 28, 2022): 045301. http://dx.doi.org/10.1063/5.0096686.

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Two-dimensional materials, such as transition metal dichalcogenides, have generated much interest due to their strain-sensitive electronic, optical, magnetic, superconducting, or topological properties. Harnessing control over their strain state may enable new technologies that operate by controlling these materials’ properties in devices such as straintronic transistors. Piezoelectric oxides have been proposed as one method to control such strain states on the device scale. However, there are few studies of how conformal 2D materials remain on oxide materials with respect to dynamic applications of the strain. Non-conformality may lead to non-optimal strain transfer. In this work, we explore this aspect of oxide-2D adhesion in the nanoscale switching of the substrate structural phase in thin 1T′-MoTe2 attached to a mixed-phase thin-film BiFeO3 (BFO), a multiferroic oxide with an electric-field induced structural phase transition that can generate mechanical strains of up to 2%. We observe that flake thickness impacts the conformality of 1T′-MoTe2 to structural changes in BFO, but below four layers, 1T′-MoTe2 fully conforms to the nanoscale BFO structural changes. The conformality of few-layer 1T′-MoTe2 suggests that BFO is an excellent candidate for deterministic, nanoscale strain control for 2D materials.

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5

Dash, Swagatika, R. N. P. Choudhary, Piyush R. Das, and Ashok Kumar. "Structural, dielectric, and multiferroic properties of (Bi0.5K0.5)(Fe0.5Nb0.5)O3." Canadian Journal of Physics 93, no. 7 (July 2015): 738–44. http://dx.doi.org/10.1139/cjp-2014-0025.

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A polycrystalline sample of (Bi0.5K0.5)(Fe0.5Nb0.5)O3 was prepared using a mixed oxide at 1000 °C. The preliminary structural analysis using X-ray diffraction data of the compound indicates the formation of a single-phase rhombohedral structure similar to that of parent BiFeO3. Microstructural and elemental analysis using a scanning electron micrograph and energy-dispersive X-ray spectroscopy, respectively, were carried out at room temperature with higher magnification exhibiting a uniform distribution of grains and stoichiometry. The appearance of hysteresis loops (P–E) confirms the existence of ferroelectricity of the sample with a high remnant polarization of (2Pr) 17.76 μCcm−2. Using impedance spectroscopy, the electrical properties of the material were investigated at a wide range of temperature (25–500 °C) and frequencies (1 kHz – 1 MHz) suggesting dielectric non-Debye-type relaxation in the material. The nature of the Nyquist plot ([Formula: see text] ∼ [Formula: see text]) shows the dominance of the grain contribution in the impedance. The bulk resistance of the compound decreases with increasing temperature, like that of a semiconductor, which shows a negative temperature coefficient of resistance (NTCR) behavior. The frequency dependence of AC conductivity suggests that that the material obeys Jonscher’s power law. Magnetic hysteresis (M–H) loop shows very weak ferromagnetic behavior at room temperature.

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6

Pattanayak, Samita, R. N. P. Choudhary, and Piyush R. Das. "Studies of electrical conductivity and magnetic properties of Bi1-xGdxFeO3 multiferroics." Journal of Advanced Dielectrics 04, no. 02 (April 2014): 1450011. http://dx.doi.org/10.1142/s2010135x14500118.

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The polycrystalline samples of Bi 1-x Gd x FeO 3 (x = 0, 0.1, and 0.2) multiferroic oxides have been synthesized by a solid-state reaction/mixed oxide technique. The preliminary X-ray structural analysis with room temperature diffraction data confirmed the formation of single-phase systems. Study of room temperature scanning electron micrograph (SEM) of the surface of the above samples exhibits a uniform distribution of plate- and rod-shaped grains throughout the sample surface with less porosity. The dielectric behavior of the materials was studied in a wide range of frequency (1 kHz–1 MHz) and temperature (30–400°C). The nature of temperature dependence of dc conductivity confirms the Arrhenius behavior of the materials. The frequency–temperature dependence of ac conductivity suggests that the material obeys Jonscher's universal power law. An increase in Gd -content results in the enhancement of spontaneous magnetization BiFeO 3 (BFO) due to the collapse of spin cycloid structure. The magnetoelectric coupling coefficient of BFO has been enhanced on Gd -substitution.

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7

Barrier, Nicolas. "Search for new tellurium and selenium oxides with potential ferroelectric and multiferroic properties." Acta Crystallographica Section A Foundations and Advances 75, a2 (August 18, 2019): e204-e204. http://dx.doi.org/10.1107/s2053273319093525.

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8

Moustafa, A. M., S. A. Gad, G. M. Turky, and L. M. Salah. "Structural, Magnetic, and Dielectric Spectroscopy Investigations of Multiferroic Composite Based on Perovskite–Spinel Approach." ECS Journal of Solid State Science and Technology 11, no. 3 (March 1, 2022): 033008. http://dx.doi.org/10.1149/2162-8777/ac5c7d.

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Multiferroic composite materials with the nominal composition (La0.8Gd0.2FeO3)1−x(Mn0.5Cu0.5Fe2O4)x, x = 0.0≤x≤1 were prepared using the co-precipition method. XRD, FTIR and Raman were utilized to investigate the structure phase, microstructural characteristics, vibrational bands. The optical properties were analyzed; the VSM was used to investigate the magnetic properties of the composites. Broadband dielectric spectroscopy is employed to investigate the dielectric and electrical performance of the prepared multiferroic composites. Rietveld refinement of the XRD patterns confirmed the orthorhombic phase for lanthanum gadolinium iron oxide (La0.8Gd0.2FeO3) and cubic phase for manganese copper ferrite (Mn0.5Cu0.5Fe2O4). The crystallite size of LGFO phase pointed out that it increases with increasing the MCFO phase, while the microstrain found to decline. The FTIR results elucidated the tetrahedral and octahedral bands. The deduced optical properties revealed that the samples have optical energy gap in the range 4.18 −4.5 eV. The magnetic properties revealed that the composites exhibit typical ferromagnetic hysteresis loops, indicating the presence of ordered magnetic structure. The frequency dependence of permittivity ε′(f) and real part of complex conductivity, σ′(f) exhibits a development of a net of micro-capacitors like behavior that stores charge carriers.

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9

Sun, Shujie, and Xiaofeng Yin. "Progress and Perspectives on Aurivillius-Type Layered Ferroelectric Oxides in Binary Bi4Ti3O12-BiFeO3 System for Multifunctional Applications." Crystals 11, no. 1 (December 29, 2020): 23. http://dx.doi.org/10.3390/cryst11010023.

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Анотація:

Driven by potentially photo-electro-magnetic functionality, Bi-containing Aurivillius-type oxides of binary Bi4Ti3O12-BiFeO3 system with a general formula of Bin+1Fen−3Ti3O3n+3, typically in a naturally layered perovskite-related structure, have attracted increasing research interest, especially in the last twenty years. Benefiting from highly structural tolerance and simultaneous electric dipole and magnetic ordering at room temperature, these Aurivillius-phase oxides as potentially single-phase and room-temperature multiferroic materials can accommodate many different cations and exhibit a rich spectrum of properties. In this review, firstly, we discussed the characteristics of Aurivillius-phase layered structure and recent progress in the field of synthesis of such materials with various architectures. Secondly, we summarized recent strategies to improve ferroelectric and magnetic properties, consisting of chemical modification, interface engineering, oxyhalide derivatives and morphology controlling. Thirdly, we highlighted some research hotspots on magnetoelectric effect, catalytic activity, microwave absorption, and photovoltaic effect for promising applications. Finally, we provided an updated overview on the understanding and also highlighting of the existing issues that hinder further development of the multifunctional Bin+1Fen−3Ti3O3n+3 materials.

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10

Li, Jun, Elena A. Medina, Judith K. Stalick, Arthur W. Sleight та M. A. Subramanian. "Structural studies of CaAl12O19, SrAl12O19, La2/3+δ Al12–δO19, and CaAl10NiTiO19 with the hibonite structure; indications of an unusual type of ferroelectricity". Zeitschrift für Naturforschung B 71, № 5 (1 травня 2016): 475–84. http://dx.doi.org/10.1515/znb-2015-0224.

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AbstractVarious oxides with the hibonite structure were synthesized and structurally analyzed using powder neutron diffraction. The structure of CaAl12O19 at 298 and 11 K shows dipoles that are apparently too dilute to order unless subjected to a suitable electric field. Magnetoplumbites, such as BaFe12O19, are isostructural with hibonite. These compounds possess ferromagnetic properties, which combined with the electric dipoles may influence multiferroic behavior. Our SrAl12O19 sample showed two distinct hexagonal phases, a major phase with the normal hibonite structure and a minor phase having a closely related structure. Our sample of the defect hibonite phase La2/3+δAl12–δO19 shows a distinctly higher δ value (0.25) vs. that reported (~0.15) for samples made from the melt. Finally, we used to advantage the negative scattering length of Ti to determine the site occupancies of Ni and Ti in CaAl10NiTiO19.

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11

SARDAR, K., K. ALI, S. ALTAF, M. SAJJAD, B. SALEEM, L. AKBAR, A. SATTAR, et al. "ENHANCED STRUCTURAL AND OPTICAL PROPERTIES OF BISMUTH FERRITE (BiFeO3) NANOPARTICLES." Digest Journal of Nanomaterials and Biostructures 15, no. 1 (January 2020): 51–57. http://dx.doi.org/10.15251/djnb.2020.151.51.

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Multiferroic Bismuth Iron Oxide (BiFeO3) nanoparticles was synthesized via sol gel method. This study demonstrated the preparation of nanoparticles of bismuth ferrite at 550ᵒC. In this method Bismuth nitrate [Bi (NO3)3.5H2O] and iron nitrate [Fe (NO3)3.9H2O] were used as starting chemical agent. In order to overcome the volatility of Bismuth at high temperature, different weight percentages of chemicals were used. Citric acid was used as chelating agent. Thermal treatment was given to the samples at 550ᵒC. Bismuth Ferrite nanoparticles showed obvious ferromagnetic properties. The size of Bismuth Ferrite nanoparticles reduced as magnetization increased. As the concentration of chemical increased at 550ᵒC the particle size was reduced due to recrystallization. Sol Gel method helped to control the size of crystals. The characterization of prepared samples of Bismuth Ferrite Nanoparticles was done by using X-ray diffraction (XRD), scanning electron microscope (SEM) and UV- visible for getting the information about surface morphology and crystallographic structure. X-ray diffraction result gave the information about the particle size and phase identification. UV- visible gave the information about the band gap energy of BiFeO3 nanoparticles. Scanning electron microscope result gave the information about surface morphology and grain size of nanoparticles at different resolutions.

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12

García-Zaldívar, O., S. Díaz-Castañón, F. J. Espinoza-Beltran, M. A. Hernández-Landaverde, G. López, J. Faloh-Gandarilla, and F. Calderón-Piñar. "BiFeO3 codoping with Ba, La and Ti: Magnetic and structural studies." Journal of Advanced Dielectrics 05, no. 04 (December 2015): 1550034. http://dx.doi.org/10.1142/s2010135x15500344.

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Анотація:

Conventional solid state reaction method, from oxides and carbonates, was employed to prepare bismuth (Bi)-based multiferroic systems. The undoped BiFeO3 (BFO) and the codoped system with Ba, La and Ti (Bi[Formula: see text]BaxFe[Formula: see text]TiyO3, Bi[Formula: see text]BaxLazFe[Formula: see text]TiyO3) with x,y,[Formula: see text] were prepared stoichiometrically and sintered at two different temperatures. The structural and magnetic properties were investigated at room temperature. XRD measurements confirm the obtaining of the rhombohedral perovskite structure of the BFO family system. For the undoped system, some reflections of undesired phases are present for two different sintering temperatures, while for the doped system only one phase is present for both temperatures. The magnetic characterization at room temperature revealed remarkable differences between the ceramic samples. The results show that for undoped BFO system, spontaneous magnetization is not observed at room temperature. Nevertheless, in doped one, a well-defined ferromagnetic behavior is observed at room temperature, possible, due to the suppression of the spatially modulated spin structure of BFO promoted by the reduction of the rhombohedral distortion and the weakening of the Bi–O bonds. The XPS results confirm the presence of oxygen vacancies and the coexistence of Fe[Formula: see text] and Fe[Formula: see text] in all the studied samples. Calorimetric measurements reveal that the dopant incorporation has not a direct effect in Néel temperature but possibly yes in ferroelectric-paraelectric transition.

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13

Delfard, Naimeh Badvi, Hamed Maleki, Asma Mohammadi Badizi, and Majid Taraz. "Enhanced Structural, Optical, and Multiferroic Properties of Rod-Like Bismuth Iron Oxide Nanoceramics by Dopant Lanthanum." Journal of Superconductivity and Novel Magnetism 33, no. 4 (November 18, 2019): 1207–14. http://dx.doi.org/10.1007/s10948-019-05294-3.

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14

Stojanovic, Nemanja, Aleksandra Kalezic-Glisovic, Aco Janicijevic, and Aleksa Maricic. "Evolution of structural and functional properties of the Fe/BaTiO3 system guided by mechanochemical and thermal treatment." Science of Sintering 52, no. 2 (2020): 163–76. http://dx.doi.org/10.2298/sos2002163s.

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Multiferroic systems are attractive to the researches worldwide due to diversity of existing applications, as well as possible novel ones. In order to contribute to understanding of the processes that take place within the structure of such a system, we subjected it to mechanochemical activation and thermal treatment. Powdery mixtures of iron and barium titanate in a mass ratio of 30% Fe and 70% BaTiO3 were activated in a planetary ball mill for time duration of 30 to 300 min and subsequently sintered at 1200?C in the atmosphere of air. During the activation the system undergoes structural phase transitions, whereby the content of iron and its oxides changes. The highest Fe content was observed in the sample activated for 270 min, with local maxima in crystallite size and microstrain values and a minimum in dislocation density. The complex dielectric permittivity changes in the applied radio frequency field, rangingfrom 176.9 pF/m in thesample activated for 90 min to 918.1 pF/m in the sample activated for 180 min. As the frequency of the field increases, an exponential decrease in the magnetic with a simultaneous increase in the electrical energy losses is noticeable. The system exhibits ferromagnetic resonance, whereby longer activation in the mill shifts the resonant frequency to higher values. Negative electrical resistance was observed in all analyzed samples. The activation time changes both the demagnetization temperature and the Curie temperature of the samples undergoing heating and cooling cycles in the external permanent magnetic field. Curie temperature is the highest in the sample activated for 240 min. Thermal treatment increases the initial magnetization of all samples, with the most pronounced increase of ~95% in the sample activated for 300 min.

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15

Pandey, R. K., H. Stern, W. J. Geerts, P. Padmini, P. Kale, Jian Dou, and R. Schad. "Room Temperature Magnetic-Semicondcutors in Modified Iron Titanates: Their Properties and Potential Microelectronic Devices." Advances in Science and Technology 54 (September 2008): 216–22. http://dx.doi.org/10.4028/www.scientific.net/ast.54.216.

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The phenomenal growths of information technology and related fields have warranted the development of new class of materials. Multifunctional oxides, magnetic-semiconductors, multiferroics and smart materials are just a few examples of such materials. They are needed for the development of novel technologies such as spintronics, magneto-electronics, radhard electronics, and advanced microelectronics. For these technologies, of particular interest are some solid solutions of ilmenite-hematite (IH) represented by (1-x) FeTiO3.xFe2O3 where x varies from 0 to 1; Mn-doped ilmenite (Mn+3-FeTiO3) and Mn-doped pseudobrookite, Mn+3-Fe2TiO5 (PsB). These multifunctional oxides are ferromagnetic with the magnetic Curie points well above the room temperature as well as wide bandgap semiconductors with band gap Eg > 2.5 eV. This paper outlines: (a) processing of device quality samples for structural, electrical and magnetic characterization, (b) fabrication and evaluation of an integrated structure for controlled magnetic switching, and (c) the response of the two terminal non-linear current-voltage (I-V) characteristics when biased by a dc voltage. Subsequently, we will identify a few microelectronic applications based on this class of oxides.

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16

Kawaguchi, Shogo, Hiroki Ishibashi, Shigeo Mori, Jungeun Kim, Kenichi Kato, Masaki Takata, Hironori Nakao, Yuichi Yamasaki, and Yoshiki Kubota. "Orbital Order and Structural Phase Transitions in Vanadium Spinel FeV2O4." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1358. http://dx.doi.org/10.1107/s2053273314086410.

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Orbital degrees of freedom plays an important role in condensed matter physics because it is strongly related with phase transitions and induces the fascinating physical properties. A spinel oxide FeV2O4is one of the peculiar examples because this compound has double orbital degrees of freedom at both Fe2+and V3+ions. Furthermore, this material represents exotic physical properties [1,2], i.e.; multiferroic, large magnetostriction, and successive structural transitions with decreasing temperature: cubic - tetragonal (c < a: tetraHT, 138K) - orthorhombic (orthoHT, 108 K) - tetragonal (c > a: tetraLT, 68 K). However, the origin of structural transitions and physical properties is controversial until now. In order to clarify the origin, we have performed synchrotron x-ray diffraction experiments at low temperatures at beamline BL02B2 (for the powder samples) in SPring-8 and BL-4C (for the single crystal) of the Photon Factory, KEK. Furthermore, we have carried out the magnetization and the specific heat measurements using polycrystalline samples and single crystal of FeV2O4. We have firstly found another orthorhombic phase (orthoLT) below 30 K in the polycrystalline sample of FeV2O4, shown in figure 1. The Rietveld analysis was performed, and the overall qualities of fittings were fairly good. In order to investigate the details of the orbital state of Fe2+and V3+in FeV2O4, we have performed the normal mode analysis, which is based on static displacements of the tetrahedron of FeO4and octahedron of VO6. In the orthoLT phase, we found the orbital order of Fe2+ions, which is mixture of 3z2-r2and y2-z2orbitals, without change of orbital order of V3+ions. This result indicates that the origin of the orthoLT phase is derived from the competition between cooperative Jahn-Teller effect and relativistic spin-orbit coupling of Fe2+ions. We also discuss the origins of the other phase transitions considering the orbital state of V3+and Fe2+ions, and then the orbital dilution effect, where the structural and magnetic properties are investigated by using powder samples substituted for Fe2+and V3+ions by other ions (Mn2+and Fe3+) with no orbital degrees of freedom.

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17

Mazzoli, Claudio, and Paolo Ghigna. "Multiferroic Properties In Complex Oxides." Current Inorganic Chemistry 3, no. 1 (February 1, 2013): 70–74. http://dx.doi.org/10.2174/1877944111303010007.

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18

Koval, V., Y. Shi, I. Skorvanek, G. Viola, R. Bures, K. Saksl, P. Roupcova, M. Zhang, Ch Jia, and H. Yan. "Cobalt-induced structural modulation in multiferroic Aurivillius-phase oxides." Journal of Materials Chemistry C 8, no. 25 (2020): 8466–83. http://dx.doi.org/10.1039/d0tc01443e.

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Анотація:

Nanoscale structural modulation with the disordered intergrowth of three- and four-layered Aurivillius phases gives rise to the ferromagnetic clustering of the FeO₆ and CoO₆ octahedra in cobalt-substituted Bi₅FeTi₃O₁₅-derived compounds.

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19

Ahmad, Javed, Shoaib Hassan, Jamshaid Alam Khan, Umair Nissar, and Hammad Abbas. "Insight into Structural and Optical Properties of Pristine and Sr2+ Doped La2NiMnO6." Proceedings of the Pakistan Academy of Sciences: A. Physical and Computational Sciences 58, no. 2 (December 27, 2021): 59–71. http://dx.doi.org/10.53560/ppasa(58-2)610.

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Double perovskites oxide (DPO) multiferroics La2-xSrxNiMnO6(x=0.0, 0.1, 0.2, 0.4, 0.6) are synthesized by sol-gel technique. The structural, optical and electrical (both DC and AC) properties of La2-xSrxNiMnO6 have been investigated by XRD and FTIR spectroscopy and two-probe resistivity and dielectric measurements as a function of temperature, respectively. The effect of doping of Strontium at A-site in double perovskites is discussed. XRD has revealed the formation of monoclinic structure of La2-xSrxNiMnO6 with space group P21 / n for x=0.0 and P21 for x=0.1, 0.2, 0.4, 0.6. The average crystallite size has been calculated to be in the range 31 to 46 nm as determined by Debye Scherrer equation. Infrared active optical phonons observed from reflectivity spectra have been analysed fitting the theoretical oscillators using Lorentz oscillator model. We have observed several well-resolved phonon modes in La2-xSrxNiMnO6 with increasing dopant concentration. Activation energy calculated using Arrhenius Plot is in the range of 0.31 to 0.18 eV, confirming the semiconducting nature of all samples. The dielectric constant and tangent loss as a function of temperature and frequency are also discussed for these multiferroics.

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20

Cho, Jae-Hyeon, and Wook Jo. "Progress in the Development of Single-Phase Magnetoelectric Multiferroic Oxides." Ceramist 24, no. 3 (September 30, 2021): 228–47. http://dx.doi.org/10.31613/ceramist.2021.24.3.03.

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Magnetoelectric (ME) multiferroics manifesting the coexistence and the coupling of ferromagnetic and ferroelectric order are appealing widespread interest owing to their fascinating physical behaviors and possible novel applications. In this review, we highlight the progress in single-phase ME multiferroic oxides research in terms of the classification depending on the physical origins of ferroic properties and the corresponding examples for each case, i.e., material by material, along with their ME multiferroic properties including saturation magnetization, spontaneous polarization, (anti)ferromagnetic/ferroelectric transition temperature, and ME coefficient. The magnetoelectrically-active applications of high expectancy are presented by citing the representative examples such as magnetoelectric random-access-memory and multiferroic photovoltaics. Furthermore, we discuss how the development of ME multiferroic oxides should proceed by considering the current research status in terms of developed materials and designed applications. We believe that this short review will provide a basic introduction for the researchers new to this field.

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21

KUMAR SWAMY, N., MANISH GUPTA, B. K. DAS, and N. PAVAN KUMAR. "STRUCTURAL AND THERMODYNAMIC PROPERTIES OF MULTIFERROIC Y0.5Dy0.5MnO3." International Journal of Modern Physics: Conference Series 22 (January 2013): 530–32. http://dx.doi.org/10.1142/s2010194513010623.

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The structural and thermodynamic properties of polycrystalline samples of Y0.5Dy0.5MnO3 were investigated in order to investigate the effect of higher magnetic moment ion over Y ion. The structural transition from hexagonal to orthorhombic is observed at very high doping of Dy ion. Heat capacity measurements were performed at 2-300K in the application of different high magnetic field and the transition indicates the spin alignment of Mn 3+( TNMn3+ ). By using heat capacity data also calculated Debye temperature of the series.

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22

Belik, Alexei A., Hitoshi Yusa, Naohisa Hirao, Yasuo Ohishi, and Eiji Takayama-Muromachi. "Structural Properties of Multiferroic BiFeO3under Hydrostatic Pressure." Chemistry of Materials 21, no. 14 (July 28, 2009): 3400–3405. http://dx.doi.org/10.1021/cm901008t.

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23

Das, Bablu Chandra, Md Feroz Alam Khan, and A. K. M. Akther Hossain. "Study of structural properties of multiferroic composites." Acta Crystallographica Section A Foundations and Advances 73, a2 (December 1, 2017): C514. http://dx.doi.org/10.1107/s2053273317090593.

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24

Shireen, Ajmala, Rana Saha, P. Mandal, A. Sundaresan, and C. N. R. Rao. "Multiferroic and magnetodielectric properties of the Al1−xGaxFeO3family of oxides." J. Mater. Chem. 21, no. 1 (2011): 57–59. http://dx.doi.org/10.1039/c0jm02688c.

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25

Ramachandran, T., Nhalil E. Rajeevan, and P. P. Pradyumnan. "Thermoelectric Property in Multiferroics." Advanced Materials Research 584 (October 2012): 157–61. http://dx.doi.org/10.4028/www.scientific.net/amr.584.157.

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Thermoelectricity has gained special interest due to its potential applications, especially the advancements in the electronic devices with very low power consumption. Thermoelectric materials can be used to make energy conversion devices that generate power from thermal sources. Multiferroic oxides, in particular cobaltates, have been actively studied as a new type of thermoelectric material (1). The crystal structure of these cobaltates offers a possibility to manipulate Seebeck coefficient, electric conductivity, and thermal conductivity to optimize the figure of merit ZT. The theoretical explanation and experimental observations by some investigators proved the candidature of multiferroic materials for thermoelectric generation. Many semiconducting multiferroic oxides are showing spin dependent Seebeck coefficient (2-3). Moreover, most of these oxides are inherently stable at high temperatures in air, making them a suitable material for high temperature applications. In this work we have investigated the multiferroic and thermoelectric properties of thinfilms of doped cobalt oxide matrices. The observations confirmed that these materials are suitable for thermoelectric generation.

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26

Drathen, Christina, Kirill Yusenko, and Serena Margadonna. "Structural modulations in multiferroic tetragonal tungsten bronze KxMnxFe1+xF3." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C52. http://dx.doi.org/10.1107/s2053273314099471.

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Multiferroic materials showing coupling of the different order parameters (ferroelectric, ferromagnetic, ferroelastic) are interesting not only from a fundamental perspective, but also from a technological point of view, e.g. for to the development of new storage technologies. However, the coexistence of (ferro)magnetism and ferroelectricity is considered a rare phenomenon. Whilst this may be true for perovskite oxides, where emptyd-shells favor the off-centering of ions but counteract magnetism, this intrinsic limitation can be avoided by moving to different structure types, and/or away from oxides. An example of non-perovskite, non-oxide multiferroic systems are the tetragonal tungsten bronze (TTB) fluorides KxM2+xM3+1+xF3(x= 0.4 – 0.6), which show coexistence of electric and magnetic ordering 1. Here we present a detailed structural study on a series of TTB fluorides, KxMnxFe1+xF3(x = 0.4 – 0.55). KMnFeF6has been previously described as tetragonalP42bcand orders ferrimagnetically belowT = 148 K 2. Additional satellite reflections were found in transmission electron microscopy experiments and attributed to ferroelastic domains arising from tilting ofMF6octahedra, but the reported bulk powder XRD measurements indicated only tetragonal symmetry 3. We used high-resolution powder diffraction techniques to reinvestigate the crystal structure as a function of temperature in comparison with DSC data. Our results reveal a structural distortion to orthorhombic symmetry (Ccc2) at room temperature, which diminished when moving to the end members of the series (x → 0.4 andx → 0.6). Although structurally subtle, this distortion may indicate a ferroelectric state, similar to KxFeF3, where ferroelectricity is observed only in the orthorhombic phase. On heating, an anomaly in thec-axis lattice parameter accompanies a phase transition to centrosymmetricP42/mbcaround 320 – 350 K, marking the transition from ferroelectric – paraelectric state.

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27

Díaz-Moreno, Carlos A., Jorge A. López, Yu Ding, A. Hurtado Macias, Chunqiang Li, and Ryan B. Wicker. "Multiferroic and Optical Properties of La0.05Li0.85NbO3 and LiNbO3 Nanocrystals." Journal of Nanotechnology 2018 (September 3, 2018): 1–13. http://dx.doi.org/10.1155/2018/3721095.

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The chemistry and physics of surfaces is an increasingly important subject. The study of surfaces is the key of many important nanotechnological applications due to the understanding of phase transitions, electronic structure, and chemical bonding. In later years, exotic phenomena that jointly involve the magnetic and electrical conductivity properties have been discovered in oxides that contain magnetic ions. Moreover, the uses of magnetic oxides in electronic technology have become so important due to the miniaturization of devices and magnetic materials with dielectric properties or vice versa being required for inductors, information storage, thin films for high-density computer memories, microwave antireflection coatings, and permanent magnets for automobile ignitions among others. On the contrary, nanotechnology developments over 10 years or so have provided intensive studies in trying to combine properties such as ferroelectric, ferromagnetic, and optics in one single-phase nanoparticles or in composite thin films; this last effort has been recently known as multiferroic. Because of this, the resurgence of nanomaterials with multiferroic and optical properties is presented in this work of one single phase in lanthanum lithium niobate (La0.05Li0.85NbO3) and lithium niobate (LiNbO3) with ferromagnetic, ferroelectric, relaxor ferroelectricity, second harmonic generation, high-temperature ferromagnetic, and magnetoelectric properties.

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28

Du, Y., Z. X. Cheng, X. L. Wang, and S. X. Dou. "Lanthanum doped multiferroic DyFeO3: Structural and magnetic properties." Journal of Applied Physics 107, no. 9 (May 2010): 09D908. http://dx.doi.org/10.1063/1.3360354.

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29

Meena, P. L., Sunita Pal, K. Sreenivas, and Ravi Kumar. "Structural and Magnetic Properties of MnCo2O4 Spinel Multiferroic." Advanced Science Letters 21, no. 9 (September 1, 2015): 2760–63. http://dx.doi.org/10.1166/asl.2015.6336.

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30

Staruch, M., D. Violette, and M. Jain. "Structural and magnetic properties of multiferroic bulk TbMnO3." Materials Chemistry and Physics 139, no. 2-3 (May 2013): 897–900. http://dx.doi.org/10.1016/j.matchemphys.2013.02.051.

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31

Ji, Kun-lang, Elena Solana-Madruga, Angel M. Arevalo-Lopez, Pascal Manuel, Clemens Ritter, Anatoliy Senyshyn, and J. Paul Attfield. "Lock-in spin structures and ferrimagnetism in polar Ni2−xCoxScSbO6 oxides." Chemical Communications 54, no. 88 (2018): 12523–26. http://dx.doi.org/10.1039/c8cc07556e.

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32

Sha, L., J. Miao, S. Z. Wu, X. G. Xu, Y. Jiang, and L. J. Qiao. "Double-perovskite multiferroic Bi2FeCrO6 polycrystalline thin film: The structural, multiferroic, and ferroelectric domain properties." Journal of Alloys and Compounds 554 (March 2013): 299–303. http://dx.doi.org/10.1016/j.jallcom.2012.11.187.

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33

Sun, Shujie, Yan Huang, Guopeng Wang, Jianlin Wang, Zhengping Fu, Ranran Peng, Randy J. Knize, and Yalin Lu. "Nanoscale structural modulation and enhanced room-temperature multiferroic properties." Nanoscale 6, no. 22 (August 5, 2014): 13494–500. http://dx.doi.org/10.1039/c4nr03542a.

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34

Das, S. R., R. N. P. Choudhary, P. Bhattacharya, R. S. Katiyar, P. Dutta, A. Manivannan, and M. S. Seehra. "Structural and multiferroic properties of La-modified BiFeO3 ceramics." Journal of Applied Physics 101, no. 3 (February 2007): 034104. http://dx.doi.org/10.1063/1.2432869.

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35

Goian, V., S. Kamba, D. Nuzhnyy, P. Vaněk, M. Kempa, V. Bovtun, K. Knížek, et al. "Dielectric, magnetic and structural properties of novel multiferroic Eu0.5Ba0.5TiO3ceramics." Journal of Physics: Condensed Matter 23, no. 2 (December 16, 2010): 025904. http://dx.doi.org/10.1088/0953-8984/23/2/025904.

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36

Kaippamagalath, Aswathi, Jasnamol P. Palakkal, Ajeesh P. Paulose, and Manoj R. Varma. "Structural and magnetic properties of multiferroic Y2NiMnO6 double perovskite." Ferroelectrics 518, no. 1 (October 3, 2017): 223–31. http://dx.doi.org/10.1080/00150193.2017.1360679.

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37

Guo, Zhengang, Liqing Pan, Chong Bi, Hongmei Qiu, Xuedan Zhao, Lihong Yang, and M. Yasir Rafique. "Structural and multiferroic properties of Fe-doped Ba0.5Sr0.5TiO3 solids." Journal of Magnetism and Magnetic Materials 325 (January 2013): 24–28. http://dx.doi.org/10.1016/j.jmmm.2012.08.023.

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38

Muneeswaran, M., P. Jegatheesan, M. Gopiraman, Ick-Soo Kim, and N. V. Giridharan. "Structural, optical, and multiferroic properties of single phased BiFeO3." Applied Physics A 114, no. 3 (April 27, 2013): 853–59. http://dx.doi.org/10.1007/s00339-013-7712-5.

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39

Wu, Y. J., Z. J. Hong, Y. Q. Lin, S. P. Gu, X. Q. Liu, and X. M. Chen. "Room temperature multiferroic Ba4Bi2Fe2Nb8O30: Structural, dielectric, and magnetic properties." Journal of Applied Physics 108, no. 1 (July 2010): 014111. http://dx.doi.org/10.1063/1.3459887.

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40

Sun, Shujie, Guopeng Wang, Yan Huang, Jianlin Wang, Ranran Peng, and Yalin Lu. "Structural transformation and multiferroic properties in Gd-doped Bi7Fe3Ti3O21ceramics." RSC Advances 4, no. 57 (June 16, 2014): 30440. http://dx.doi.org/10.1039/c4ra04945d.

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41

Ye, Wei, Guoqiang Tan, Xia Yan, Huijun Ren, and Ao Xia. "Structural and multiferroic properties of Bi0.92−xHo0.08CaxFe0.97Mn0.03O3 thin film." Ceramics International 42, no. 1 (January 2016): 481–89. http://dx.doi.org/10.1016/j.ceramint.2015.08.134.

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42

Gervacio-Arciniega, J. J., E. Murillo-Bracamontes, O. Contreras, J. M. Siqueiros, O. Raymond, A. Durán, D. Bueno-Baques, et al. "Multiferroic YCrO3 thin films: Structural, ferroelectric and magnetic properties." Applied Surface Science 427 (January 2018): 635–39. http://dx.doi.org/10.1016/j.apsusc.2017.09.011.

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43

Negi, P., G. Dixit, H. M. Agrawal, and R. C. Srivastava. "Structural, Optical and Magnetic Properties of Multiferroic GdMnO3 Nanoparticles." Journal of Superconductivity and Novel Magnetism 26, no. 5 (December 19, 2012): 1611–15. http://dx.doi.org/10.1007/s10948-012-1870-0.

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44

Dabas, Samiksha, Prachi Chaudhary, Manish Kumar, S. Shankar, and O. P. Thakur. "Structural, microstructural and multiferroic properties of BiFeO3–CoFe2O4 composites." Journal of Materials Science: Materials in Electronics 30, no. 3 (December 17, 2018): 2837–46. http://dx.doi.org/10.1007/s10854-018-0560-5.

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45

Zhao, Y., J. Miao, X. B. Meng, F. Weng, X. G. Xu, Y. Jiang, and S. G. Wang. "Butterfly-shaped multiferroic BiFeO3@BaTiO3 core–shell nanotubes: the interesting structural, multiferroic, and optical properties." Journal of Materials Science: Materials in Electronics 24, no. 5 (November 2, 2012): 1439–45. http://dx.doi.org/10.1007/s10854-012-0947-7.

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46

Li, Zhengxin, Zhenhua Wang, Rongli Gao, Wei Cai, Gang Chen, Xiaoling Deng, and Chunlin Fu. "Dielectric, ferroelectric and magnetic properties of Bi0.78La0.08Sm0.14Fe0.85Ti0.15O3 ceramics prepared at different sintering conditions." Processing and Application of Ceramics 12, no. 4 (2018): 394–402. http://dx.doi.org/10.2298/pac1804394l.

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Although BiFeO3 (BFO) has attracted great attention due to its special physical properties as a typical single phase multiferroic material, the application is limited due to the formation of impurities, defects and so forth. Herein, we report improved multiferroic properties of Bi0.78La0.08Sm0.14Fe0.85Ti0.15O3 (BLSFTO) ceramics by combination of co-doping and sintering schedule. BLSFTO multiferroic ceramics were prepared by using the conventional solid state reaction method and the effect of sintering time (2, 5, 10, 20 and 30 h) on the structural, dielectric and multiferroic properties was investigated systematically. The result indicates that stable BLSFTO phase with perovskite structure was formed for all the samples. Only some impurities such as Bi2O4 can be observed when the sintering time is longer than 20 h, indicating that the sintering time can induce structural changes in BLSFTO and too long sintering time can remarkably increase the secondary phases. In addition, the frequency dependent dielectric properties show that sintering time has distinct effect on the frequency stability and the relaxation process. The result demonstrates that the enhanced magnetization, improved dielectric and ferroelectric properties may be correlated with the structural transformation, impurities, oxygen vacancies and grain morphology.

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47

Fiebig, Manfred. "Phase engineering in oxides by interfaces." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 370, no. 1977 (October 28, 2012): 4972–88. http://dx.doi.org/10.1098/rsta.2012.0204.

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Optical second harmonic generation and piezoresponse force microscopy are used to investigate manifestations of ordered states directly related to the presence of an oxide interface. Three examples, each with a very different scope, are reviewed in order to highlight the richness of interface-related phenomena in oxides. (i) The orbital states involved in the emergence of an interfacial conducting state in LaAlO 3 /SrTiO 3 heterostructures are investigated, which reveal a surprising decoupling of orbital and transport properties; (ii) the distribution of ferroelectric and antiferromagnetic domains in epitaxial films of the multiferroic hexagonal manganites is investigated, which reveals striking differences to the corresponding bulk crystals; and (iii) the distribution of trimerization–polarization domains in the hexagonal manganites is investigated, which reveals the presence of topologically protected domain walls with properties different from the bulk.

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48

Guo, Er-Jia, Ryan Desautels, David Keavney, Manuel A. Roldan, Brian J. Kirby, Dongkyu Lee, Zhaoliang Liao, et al. "Nanoscale ferroelastic twins formed in strained LaCoO3 films." Science Advances 5, no. 3 (March 2019): eaav5050. http://dx.doi.org/10.1126/sciadv.aav5050.

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The coexistence and coupling of ferroelasticity and magnetic ordering in a single material offers a great opportunity to realize novel devices with multiple tuning knobs. Complex oxides are a particularly promising class of materials to find multiferroic interactions due to their rich phase diagrams, and are sensitive to external perturbations. Still, there are very few examples of these systems. Here, we report the observation of twin domains in ferroelastic LaCoO3 epitaxial films and their geometric control of structural symmetry intimately linked to the material’s electronic and magnetic states. A unidirectional structural modulation is achieved by selective choice of substrates having twofold rotational symmetry. This modulation perturbs the crystal field–splitting energy, leading to unexpected in-plane anisotropy of orbital configuration and magnetization. These findings demonstrate the use of structural modulation to control multiferroic interactions and may enable a great potential for stimulation of exotic phenomena through artificial domain engineering.

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49

Zhang, Hong-Guang, Xiao-Chen Ma, and Liang Xie. "The structural and magnetic properties of Sr-doped multiferroic CaMn7O12." International Journal of Modern Physics B 29, no. 30 (November 18, 2015): 1550221. http://dx.doi.org/10.1142/s0217979215502215.

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The structural and magnetic properties of Sr-doped multiferroic [Formula: see text] were investigated by X-ray diffraction (XRD), Raman spectra, X-ray absorption spectroscopy and temperature dependence of magnetization. The XRD indicates that the samples are rhombohedral lattice (space group [Formula: see text]) with small additional phase [Formula: see text]. The refined lattice parameters of the main phase increases by the Sr doping. The Raman spectra demonstrate the phonon vibration direction is affected, which is probably due to the rotation of [Formula: see text] octahedral. However, as the valence state of Sr and Ca is same at +2, the samples with doping show nonvariation of peak position at Mn [Formula: see text] X-ray absorption spectra, indicating that the ratio of [Formula: see text] and [Formula: see text] ions is unchanged. And the magnetic transition temperature both at [Formula: see text] and [Formula: see text] is also not tunable because the amount of magnetic interaction between [Formula: see text] and [Formula: see text] is not influenced by doping Sr ion. Only the enhancement of the magnetization at low temperature is observed, which is the same as the effect caused by external magnetic fields. An unsaturated wasp-waist type hysteresis loop is observed, indicating the competition between ferromagnetic-like and antiferromagnetic order.

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50

Tomar, M. S., A. Charris-Hernández, D. Barrionuevo, and A. Kumar. "Structural and Multiferroic Properties of Bi3.4La0.6Ti3O12/CoFe2O4 Composite Thin Films." Integrated Ferroelectrics 157, no. 1 (June 16, 2014): 63–70. http://dx.doi.org/10.1080/10584587.2014.912081.

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