Journal articles: 'Magnetic Properties - Exotic Transition Metal Oxides'

1

Niu, Xu, Bin-Bin Chen, Ni Zhong, Ping-Hua Xiang, and Chun-Gang Duan. "Topological Hall effect in SrRuO₃ thin films and heterostructures." Journal of Physics: Condensed Matter 34, no. 24 (April 14, 2022): 244001. http://dx.doi.org/10.1088/1361-648x/ac60d0.

Full text

Abstract:

Abstract Transition metal oxides hold a wide spectrum of fascinating properties endowed by the strong electron correlations. In 4d and 5d oxides, exotic phases can be realized with the involvement of strong spin–orbit coupling (SOC), such as unconventional magnetism and topological superconductivity. Recently, topological Hall effects (THEs) and magnetic skyrmions have been uncovered in SrRuO3 thin films and heterostructures, where the presence of SOC and inversion symmetry breaking at the interface are believed to play a key role. Realization of magnetic skyrmions in oxides not only offers a platform to study topological physics with correlated electrons, but also opens up new possibilities for magnetic oxides using in the low-power spintronic devices. In this review, we discuss recent observations of THE and skyrmions in the SRO film interfaced with various materials, with a focus on the electric tuning of THE. We conclude with a discussion on the directions of future research in this field.

APA, Harvard, Vancouver, ISO, and other styles

2

ALONSO, J. A., M. J. MARTÍNEZ-LOPE, C. DE LA CALLE, J. SÁNCHEZ-BENÍTEZ, M. RETUERTO, A. AGUADERO, and M. T. FERNANDEZ-DÍAZ. "HIGH-PRESSURE SYNTHESIS AND CHARACTERIZATION OF NEW METASTABLE OXIDES." Functional Materials Letters 04, no. 04 (December 2011): 333–36. http://dx.doi.org/10.1142/s1793604711002123.

Full text

Abstract:

Many transition-metal oxides in elevated valence states [e.g. Mn(V), Co(IV), Ni(III), Cu(III) ] present a metastable character and, given the difficulty of their synthesis, have been relatively little studied. However, they are very interesting materials presenting strong electronic correlations that are bound to exotic properties such as superconductivity, metal behavior, metal–insulator transitions or colossal magnetoresistance. The metastability of these compounds requires special synthesis conditions such as the application of high pressure. In the last years, we have prepared and investigated a good number of materials belonging to several families such as RNiO3 (R = rare earths), Ba3Mn2O8 , (Ba,Sr)CoO3 , La2(Ni,Co)O4+δ , etc. In the study and correct characterization of these oxides it has been decisive the use of elastic neutron diffraction, most of the times in powder samples. This technique has allowed us to access the structural details typically related to the octahedral tilting in perovskite structures, the oxygen stoichiometry and order–disorder of the oxygen sublattice, the distinction between close elements in the Periodic Table, the resolution of magnetic structures and, in general, the establishment of a correlation between the structure and the properties of interest. This letter is organized around the binomial "high-pressure synthesis" and "characterization by neutron diffraction" and illustrated with some selected examples among the metastable materials above mentioned.

APA, Harvard, Vancouver, ISO, and other styles

3

Tokura, Yoshinori. "Optical and magnetic properties of transition metal oxides." Current Opinion in Solid State and Materials Science 3, no. 2 (April 1998): 175–80. http://dx.doi.org/10.1016/s1359-0286(98)80085-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Hattori, Azusa N., Ai I. Osaka, Ken Hattori, Yasuhisa Naitoh, Hisashi Shima, Hiroyuki Akinaga, and Hidekazu Tanaka. "Investigation of Statistical Metal-Insulator Transition Properties of Electronic Domains in Spatially Confined VO2 Nanostructure." Crystals 10, no. 8 (July 22, 2020): 631. http://dx.doi.org/10.3390/cryst10080631.

Full text

Abstract:

Functional oxides with strongly correlated electron systems, such as vanadium dioxide, manganite, and so on, show a metal-insulator transition and an insulator-metal transition (MIT and IMT) with a change in conductivity of several orders of magnitude. Since the discovery of phase separation during transition processes, many researchers have been trying to capture a nanoscale electronic domain and investigate its exotic properties. To understand the exotic properties of the nanoscale electronic domain, we studied the MIT and IMT properties for the VO2 electronic domains confined into a 20 nm length scale. The confined domains in VO2 exhibited an intrinsic first-order MIT and IMT with an unusually steep single-step change in the temperature dependent resistivity (R-T) curve. The investigation of the temperature-sweep-rate dependent MIT and IMT properties revealed the statistical transition behavior among the domains. These results are the first demonstration approaching the transition dynamics: the competition between the phase-transition kinetics and experimental temperature-sweep-rate in a nano scale. We proposed a statistical transition model to describe the correlation between the domain behavior and the observable R-T curve, which connect the progression of the MIT and IMT from the macroscopic to microscopic viewpoints.

APA, Harvard, Vancouver, ISO, and other styles

5

Siwen, Li, Meng Jian, and Ren Yufang. "The electrical and magnetic properties of lanthanide alkaline-earth transition-metal oxides." Materials Research Bulletin 34, no. 10-11 (July 1999): 1569–75. http://dx.doi.org/10.1016/s0025-5408(99)00179-8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Du, Yongping, and Xiangang Wan. "The novel electronic and magnetic properties in 5d transition metal oxides system." Computational Materials Science 112 (February 2016): 416–27. http://dx.doi.org/10.1016/j.commatsci.2015.09.036.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Umek, Polona, Andrej Zorko, and Denis Arcon. "ChemInform Abstract: Magnetic Properties of Transition-Metal Oxides: from Bulk to Nano." ChemInform 42, no. 42 (September 27, 2011): no. http://dx.doi.org/10.1002/chin.201142214.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Gupta, Akanksha, Rui Zhang, Pramod Kumar, Vinod Kumar, and Anup Kumar. "Nano-Structured Dilute Magnetic Semiconductors for Efficient Spintronics at Room Temperature." Magnetochemistry 6, no. 1 (March 16, 2020): 15. http://dx.doi.org/10.3390/magnetochemistry6010015.

Full text

Abstract:

In recent years, many efforts have been made to develop advanced metal oxide semiconductor nanomaterials with exotic magnetic properties for modern applications w.r.t traditional analogues. Dilute magnetic semiconductor oxides (DMSOs) are promising candidates for superior control over the charge and spin degrees of freedom. DMSOs are transparent, wide band gap materials with induced ferromagnetism in doping, with a minor percentage of magnetic 3d cation to create a long-range antiferromagnetic order. Although significant efforts have been carried out to achieve DMSO with ferromagnetic properties above room temperature, it is a great challenge that still exists. However, TiO2, SnO2, ZnO and In2O3 with wide band gaps of 3.2, 3.6, 3.2 and 2.92 eV, respectively, can host a broad range of dopants to generate various compositions. Interestingly, a reduction in the size of these binary oxides can induce ferromagnetism, even at room temperature, due to the grain boundary, presence of defects and oxygen vacancies. The present review provides a panorama of the structural analysis and magnetic properties of DMSOs based on binary metal oxides nanomaterials with various ferromagnetic or paramagnetic dopants, e.g., Co, V, Fe and Ni, which exhibit enhanced ferromagnetic behaviors at room temperature.

APA, Harvard, Vancouver, ISO, and other styles

9

Maignan, A., W. Kobayashi, S. Hébert, G. Martinet, D. Pelloquin, N. Bellido, and Ch Simon. "Transition-Metal Oxides with Triangular Lattices: Generation of New Magnetic and Electronic Properties." Inorganic Chemistry 47, no. 19 (October 6, 2008): 8553–61. http://dx.doi.org/10.1021/ic8006926.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Bergo, P., W. M. Pontuschka, J. M. Prison, C.C. Motta, and J. R. Martinelli. "Dielectric properties of barium phosphate glasses doped with transition metal oxides." Journal of Non-Crystalline Solids 348 (November 2004): 84–89. http://dx.doi.org/10.1016/j.jnoncrysol.2004.08.130.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Witte, Ralf, Abhishek Sarkar, Leonardo Velasco, Robert Kruk, Richard A. Brand, Benedikt Eggert, Katharina Ollefs, Eugen Weschke, Heiko Wende, and Horst Hahn. "Magnetic properties of rare-earth and transition metal based perovskite type high entropy oxides." Journal of Applied Physics 127, no. 18 (May 14, 2020): 185109. http://dx.doi.org/10.1063/5.0004125.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

HARA, Shigeo, and Hirohiko SATO. "Hydrothermal Synthesis of Transition Metal Oxides and Hydroxides and Study of Their Magnetic Properties." Review of High Pressure Science and Technology 24, no. 3 (2014): 223–29. http://dx.doi.org/10.4131/jshpreview.24.223.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Chudnovskii, F. A., A. L. Pergament, D. A. Schaefer, and G. B. Stefanovich. "Effect of Laser Irradiation on the Properties of Transition Metal Oxides." Journal of Solid State Chemistry 118, no. 2 (September 1995): 417–18. http://dx.doi.org/10.1006/jssc.1995.1363.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Tsuchiya, Toshio, Mitsuya Otonari, and Takashi Ariyama. "Internal friction and electrical properties in phosphate glasses containing transition metal oxides." Journal of Non-Crystalline Solids 95-96 (December 1987): 1001–8. http://dx.doi.org/10.1016/s0022-3093(87)80709-3.

Full text

APA, Harvard, Vancouver, ISO, and other styles

15

Shimakawa, Yuichi. "Multiple magnetic interactions in ordered perovskite-structure oxides." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C981. http://dx.doi.org/10.1107/s2053273314090184.

Full text

Abstract:

Cation ordering in transition-metal oxides often drastically modifies their properties. We focus on A-and-B-site-ordered quadruple perovskite-structure oxides AA'3B2B'2O12, in which transition-metal ions are included at the A', B, and B' sites in an ordered manner. In such compounds A'-A', A'-B, A'-B', and B-B' interactions compete with each other and play important role in giving rise to unusual properties. The A-and-B-site-ordered quadruple perovskite CaCu3Fe2Sb2O12with magnetic Fe3+at the B site and nonmagnetic Sb5+at the B' site was successfully synthesized under a high-pressure and high-temperature condition. The B-site Fe3+spin sublattice adapts a tetrahedral framework and the Fe3+-Fe3+antiferromagnetic interaction causes geometrical spin frustration as seen in the double perovskite Ca2FeSbO6. With the introduction of Cu2+into the A' site, the frustration is relieved by strong antiferromagnetic A'(Cu2+)-B(Fe3+) interaction, leading to a ferrimagnetic ordering below 160 K. When B'-site Sb5+was replaced with Re5+, another A-and-B-site-ordered quadruple perovskite CaCu3Fe2Re2O12was synthesized by a high-pressure technique. The compound contains magnetic Fe3+at the B site and Re5+at the B' sites, and strong antiferromagnetic A'(Cu2+)-B'(Re5+) interaction overcomes the A'(Cu2+)-B(Fe3+) interaction, leading to a ferrimagnetism with the ferromagnetic A'(Cu2+)-B(Fe3+) spin arrangement below 550 K. More importantly, the electronic structure of CaCu3Fe2Re2O12is half metallic and the compound shows large magnetoresistance by the spin-dependent transport.

APA, Harvard, Vancouver, ISO, and other styles

16

Kan, Er Jun. "Electronic Structures in LaTiO₃/LaAlO₃ Multilayers." Advanced Materials Research 771 (September 2013): 7–11. http://dx.doi.org/10.4028/www.scientific.net/amr.771.7.

Full text

Abstract:

We demonstrate the existence of a hidden degree of freedom controlling the orbitalordering in [LaTiO1/[LaAlO5 multilayers with comprehensive density-functional theorycalculations. The orbitals of two-dimensional (2D) 3d1state of Ti atoms in the multilayers alwayscontain large dxy components, which is unexpected from crystal field theory (first Jahn-Tellerdistortion). The competition between first and second Jahn-Teller distortion induces variousmagnetic properties. Thus, transition-metal oxides/non-transition-metal oxides multilayers mayprovide an important direction to manipulate the spin and orbital ordering in magnetic materials.

APA, Harvard, Vancouver, ISO, and other styles

17

Orlov, Yu S., S. V. Nikolaev, and S. G. Ovchinnikov. "Magnetic Properties and Spin Crossover in Transition Metal Oxides with d5 Ions at High Pressures." Journal of Experimental and Theoretical Physics 129, no. 6 (December 2019): 1062–69. http://dx.doi.org/10.1134/s1063776119120185.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Hong, Woong-Ki, SeungNam Cha, Jung Inn Sohn, and Jong Min Kim. "Metal-Insulator Phase Transition in Quasi-One-Dimensional VO2Structures." Journal of Nanomaterials 2015 (2015): 1–15. http://dx.doi.org/10.1155/2015/538954.

Full text

Abstract:

The metal-insulator transition (MIT) in strongly correlated oxides has attracted considerable attention from both theoretical and experimental researchers. Among the strongly correlated oxides, vanadium dioxide (VO2) has been extensively studied in the last decade because of a sharp, reversible change in its optical, electrical, and magnetic properties at approximately 341 K, which would be possible and promising to develop functional devices with advanced technology by utilizing MITs. However, taking the step towards successful commercialization requires the comprehensive understanding of MIT mechanisms, enabling us to manipulate the nature of transitions. In this regard, recently, quasi-one-dimensional (quasi-1D) VO2structures have been intensively investigated due to their attractive geometry and unique physical properties to observe new aspects of transitions compared with their bulk counterparts. Thus, in this review, we will address recent research progress in the development of various approaches for the modification of MITs in quasi-1D VO2structures. Furthermore, we will review recent studies on realizing novel functional devices based on quasi-1D VO2structures for a wide range of applications, such as a gas sensor, a flexible strain sensor, an electrical switch, a thermal memory, and a nonvolatile electrical memory with multiple resistance.

APA, Harvard, Vancouver, ISO, and other styles

19

Streltsov, Sergey V., and Daniel I. Khomskii. "Covalent bonds against magnetism in transition metal compounds." Proceedings of the National Academy of Sciences 113, no. 38 (September 6, 2016): 10491–96. http://dx.doi.org/10.1073/pnas.1606367113.

Full text

Abstract:

Magnetism in transition metal compounds is usually considered starting from a description of isolated ions, as exact as possible, and treating their (exchange) interaction at a later stage. We show that this standard approach may break down in many cases, especially in 4d and 5d compounds. We argue that there is an important intersite effect—an orbital-selective formation of covalent metal–metal bonds that leads to an “exclusion” of corresponding electrons from the magnetic subsystem, and thus strongly affects magnetic properties of the system. This effect is especially prominent for noninteger electron number, when it results in suppression of the famous double exchange, the main mechanism of ferromagnetism in transition metal compounds. We study this mechanism analytically and numerically and show that it explains magnetic properties of not only several 4d–5d materials, including Nb2O2F3 and Ba5AlIr2O11, but can also be operative in 3d transition metal oxides, e.g., in CrO2 under pressure. We also discuss the role of spin–orbit coupling on the competition between covalency and magnetism. Our results demonstrate that strong intersite coupling may invalidate the standard single-site starting point for considering magnetism, and can lead to a qualitatively new behavior.

APA, Harvard, Vancouver, ISO, and other styles

20

Assadi, M. Hussein N., and Yasuteru Shigeta. "The effect of octahedral distortions on the electronic properties and magnetic interactions in O3 NaTMO2 compounds (TM = Ti–Ni & Zr–Pd)." RSC Advances 8, no. 25 (2018): 13842–49. http://dx.doi.org/10.1039/c8ra00576a.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Romanenko, A. I., G. E. Chebanova, Tingting Chen, Wenbin Su, and Hongchao Wang. "Review of the thermoelectric properties of layered oxides and chalcogenides." Journal of Physics D: Applied Physics 55, no. 14 (December 3, 2021): 143001. http://dx.doi.org/10.1088/1361-6463/ac3ce6.

Full text

Abstract:

Abstract The current state of investigation on thermoelectric properties of layered chalcogenides and oxides is considered. The relationship between the quasi-two-dimensionality of electronic transport properties and thermoelectric properties is confirmed. A decrease in the dimension of electron transport from three-dimensional to quasi-two-dimensional in materials with a layered structure increases the thermopower with a slight change in electrical conductivity. The bismuth tellurides, bismuth selenides and its alloys are currently one of the outstanding state of the art bulk thermoelectric materials with layered structure. Layered transition metal dichalcogenides MX2 (M is a transition metal, X is a chalcogen) are efficient thermoelectric materials at higher temperatures (500–800 K). In these materials, an increase in thermoelectric properties associated with the two-dimensionalization of electron transport is also observed. Layered monochalcogenides MX (M = Sn, Pb, Ge; X = S, Se, Te) are also a promising class of thermoelectric materials. In SnSe single crystals, Z T ∼ 2.6 is obtained at 923 K due to the very low thermal conductivity along the b axis (0.23 W (m K)−1 at 973 K). Layered chalcogenides CuCrX2 (X = S, Se, Te) containing magnetic Cr atoms are effective thermoelectrics at higher temperatures (up to 800 K) due to the presence of phonon glass–electron crystal state led to a significant decrease in thermal conductivity at high temperatures. Magnetic atoms in CuCrX2 compounds lead to the presence of magnetic phase transitions affecting their thermoelectric properties. Interest in oxide-based thermoelectric materials has significantly increased due to their stability in air and higher temperatures for maximum efficiency. The most promising thermoelectric oxide materials Ca3Co4O9, Na x CoO2, Bi2Ca2Co2O x , and CaCo2O4 have a layered structure and contain magnetic Co atoms leading to magnetic ordering and influence on thermoelectric properties. The presence of phase transitions affects the thermoelectric parameters of thermoelectrics and the thermoelectric figure of merit ZT.

APA, Harvard, Vancouver, ISO, and other styles

22

Andriotis, Antonis N., and Madhu Menon. "Electronic and magnetic properties of the CuO4- and Co2CuO10-complexes in diluted magnetic semiconductors and transition metal oxides." Materials Research Express 6, no. 8 (May 21, 2019): 086108. http://dx.doi.org/10.1088/2053-1591/ab1620.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Provost, J., Ch Simon, M. Hervieu, D. Groult, V. Hardy, F. Studer, and M. Toulemonde. "Swift, Heavy Ions in Insulating and Conducting Oxides: Tracks and Physical Properties." MRS Bulletin 20, no. 12 (December 1995): 22–28. http://dx.doi.org/10.1557/s0883769400045863.

Full text

Abstract:

Transition metal oxides belong to the class of iono-covalent materials in which electrons are, to first order, localized in tight metal-oxygen bonds. They appear to be quite different from classical metals in which electrons are assumed to be delocalized in a free electron gas. Nevertheless, due to exchange interactions and hybridization of atomic orbitals, oxides exhibit many interesting physical properties like magnetic ordering and various electron transport properties that extend from wide gap insulators to narrow band conductors and high-temperature superconducting (HTS) superconductors. This class of materials appears well-suited to the study of the damage induced by heavy ion irradiation and its consequence on physical properties like electrical resistivity.In this article, we will describe the results of heavy ion irradiations in magnetic oxides, exhibiting a wide palette of electron transport properties from insulators to metals through hopping semiconductors and in HTS copper oxides that are narrow-band metals above Tc. We will show that heavy ion irradiation, in addition to disordering matter, can induce changes in some physical properties like magnetic ordering and orientation of magnetic fields, and can produce large increases of the critical current. To account for these results, the thermal spike model will be considered as a possible way to understand the damage creation in iono-covalent compounds.

APA, Harvard, Vancouver, ISO, and other styles

24

Khan, M. N., M. A. Hassan, and C. A. Hogarth. "The electronic and optical properties of germanium tellurite glasses containing various transition metal oxides." Physica Status Solidi (a) 106, no. 1 (March 16, 1988): 191–200. http://dx.doi.org/10.1002/pssa.2211060123.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

OOMI, G., S. KAJI, Y. TOMIOKA, and Y. TOKURA. "HIGH PRESSURE STUDY OF NOVEL ELECTRONIC PROPERTIES IN Sr2Fe(W1-xMox)O6 NEAR METAL-INSULATOR TRANSITION." International Journal of Modern Physics B 21, no. 18n19 (July 30, 2007): 3279–84. http://dx.doi.org/10.1142/s0217979207044378.

Full text

Abstract:

Electrical resistivities of double perovskite oxides Sr 2 Fe ( W 1-x Mo x) O 6 have been measured at high pressure and high magnetic field to elucidate the transport properties of these materials. It is found that the main mechanism of the transport in the semiconducting phase is variable range hopping conduction and the insulating properties are suppressed by high pressure to show a crossover to metallic state. The magnetoresistances of these oxides are revealed to decrease at high pressure above 1 GPa. Extremely large Grüneisen parameters are found near x = 0.2, where the metal-insulator transition occurs. The origin for these properties will be briefly discussed in connection with the phase diagram.

APA, Harvard, Vancouver, ISO, and other styles

26

Zheng, Ming, Pengfei Guan, Yaping Qi, and Litong Guo. "Straintronic effect on electronic transport and metal–insulator transition in correlated metal films by electric field." Applied Physics Letters 120, no. 16 (April 18, 2022): 161603. http://dx.doi.org/10.1063/5.0082879.

Full text

Abstract:

Tuning the electronic and magnetic properties of strongly correlated oxides by exerting an electric field is of great significance for understanding the mechanisms of striking quantum phenomena and delivering low-dissipation electronic devices. Here, we demonstrate a linear suppression of electrical resistivity for correlated metallic SrVO3 epitaxial films in a continuous and reversible fashion through the converse piezoelectric response-generated linear lateral compressive strain of ferroelectric Pb(Mg1/3Nb2/3)O3-PbTiO3 substrates. By precisely tailoring the polarization domain configuration of the substrate, a lateral tensile strain can also be dynamically induced into films and, thus, can robustly increase the resistivity due to reduced effective electronic bandwidth and enhanced electron–electron interaction. Particularly, the electrically triggered nonvolatile opening and closing of a metal–insulator transition is driven by the ferroelastic strain-controlled Mott gap. Our findings illustrate the vital role of an electric field in controlling the lattice degree of freedom and electron correlation and provide a framework for exploring the essential physics of the straintronic effect in correlated metallic oxides.

APA, Harvard, Vancouver, ISO, and other styles

27

EVARESTOV, R. A., A. KALINKO, A. KUZMIN, M. LOSEV, and J. PURANS. "FIRST-PRINCIPLES LCAO CALCULATIONS ON 5D TRANSITION METAL OXIDES: ELECTRONIC AND PHONON PROPERTIES." Integrated Ferroelectrics 108, no. 1 (October 22, 2009): 1–10. http://dx.doi.org/10.1080/10584580903323990.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Terny, S., and M. A. Frechero. "Understanding how the mixed alkaline-earth effect tunes transition metal oxides-tellurite glasses properties." Physica B: Condensed Matter 583 (April 2020): 412054. http://dx.doi.org/10.1016/j.physb.2020.412054.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Oh, Sunyoung, You Kyung Kim, Chan Ho Jung, Won Hui Doh, and Jeong Young Park. "Effect of the metal–support interaction on the activity and selectivity of methanol oxidation over Au supported on mesoporous oxides." Chemical Communications 54, no. 59 (2018): 8174–77. http://dx.doi.org/10.1039/c8cc04295k.

Full text

Abstract:

To elucidate the factors affecting the catalytic properties of supported Au catalysts on the metal oxide support we investigated Au NPs deposited on crystallized mesoporous transition-metal oxides (m-oxides: Co₃O₄, NiO, and α-Fe₂O₃) prepared using the nanocasting method.

APA, Harvard, Vancouver, ISO, and other styles

30

Zhang, Qin, Heng Chang Qian, Juan Pei, and Suo Jia Yuan. "Competing Effects of Band Filling and Steric Factors on Magnetic and Transport Properties of Double Perovskite." Advanced Materials Research 490-495 (March 2012): 325–28. http://dx.doi.org/10.4028/www.scientific.net/amr.490-495.325.

Full text

Abstract:

Ordered double perovskite oxides (Sr2-3xLa2xBax)FeMoO6 (0≤x≤0.3) have been investigated in this work. X-ray powder diffraction reveals that the crystal structure of the compounds changes from a tetragonal I4/m lattice to a cubic Fm m lattice around x=0.2. Due to the electron doping, the lattice constants increase with x. Owing to the competing contribution of electron doping and steric effect, Curie temperature of the compounds is almost unchanged. The resistivity of the parent compound shows a semiconducting behavior below room temperature, but those of the doped samples exhibit a metal-semiconductor transition. A correlation between the resistivity and metal-semiconducting transition temperature (TM-S) is observed. The resistivity and TM-S of the compounds decrease with x for x  0.2 and increase for x≥0.2.

APA, Harvard, Vancouver, ISO, and other styles

31

Bagabas, Abdulaziz A., Khalil A. Ziq, Ahmad F. Salem, and Emad S. Addurihem. "Magnetic Properties of Some Hydrated Transition Metal Oxide and Hydroxide Nanoparticles Synthesized in Different Media." Advanced Materials Research 123-125 (August 2010): 727–30. http://dx.doi.org/10.4028/www.scientific.net/amr.123-125.727.

Full text

Abstract:

Nanoscale particle size of metal oxides and hydroxides showed enhanced various physical properties and performance. We established a simple, cost-effective, room-temperature (RT) precipitation method for the preparation of the magnetic, first-raw transition metal (TM) hydrated oxide and hydroxide nanoparticles. This method is based on the use of the TM nitrate, as the metal source, and cyclohexylamine (CHA), as a precipitating agent, either in the water (H2O) or ethanol (EtOH) medium. We found that the precipitation medium and the identity of precipitated TM strongly affect the morphology, particle size, and magnetism of the product. The morphology varies from spherical, to rectangular, to rod shape; while the size varies in the range of 5-30 nm. All samples showed paramagnetic behavior with Curie temperatures span over a wide range (20-150K). Huge hysteresis looses has been observed for manganese (Mn) sample, prepared in H2O. The coercively (Hc) at 4.2K for this sample is about 1.5T, which is comparable to the strongest permanent magnets (Nd-based magnets) available at room temperature. The energy product (Hc*MR) is about 4.5*105 (emu/g)Oe.

APA, Harvard, Vancouver, ISO, and other styles

32

Orlov, Yu S., S. V. Nikolaev, and S. G. Ovchinnikov. "Erratum to: Magnetic Properties and Spin Crossover in Transition Metal Oxides with d5 Ions at High Pressures." Journal of Experimental and Theoretical Physics 131, no. 2 (August 2020): 374. http://dx.doi.org/10.1134/s1063776120320011.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Zhang, Kai, Kai Du, Hao Liu, X. G. Zhang, Fanli Lan, Hanxuan Lin, Wengang Wei, et al. "Manipulating electronic phase separation in strongly correlated oxides with an ordered array of antidots." Proceedings of the National Academy of Sciences 112, no. 31 (July 20, 2015): 9558–62. http://dx.doi.org/10.1073/pnas.1512326112.

Full text

Abstract:

The interesting transport and magnetic properties in manganites depend sensitively on the nucleation and growth of electronic phase-separated domains. By fabricating antidot arrays in La0.325Pr0.3Ca0.375MnO3 (LPCMO) epitaxial thin films, we create ordered arrays of micrometer-sized ferromagnetic metallic (FMM) rings in the LPCMO films that lead to dramatically increased metal–insulator transition temperatures and reduced resistances. The FMM rings emerge from the edges of the antidots where the lattice symmetry is broken. Based on our Monte Carlo simulation, these FMM rings assist the nucleation and growth of FMM phase domains increasing the metal–insulator transition with decreasing temperature or increasing magnetic field. This study points to a way in which electronic phase separation in manganites can be artificially controlled without changing chemical composition or applying external field.

APA, Harvard, Vancouver, ISO, and other styles

34

Stroud, R. M., and J. H. Scott. "Valence Mapping of Particulate 3D-Transition Metal Oxides Using Energyfiltered Transmission Electron Microscopy." Microscopy and Microanalysis 6, S2 (August 2000): 176–77. http://dx.doi.org/10.1017/s1431927600033377.

Full text

Abstract:

Particulate, mixed-valence transition metal oxides are frequently used for battery, catalytic and magnetic applications. For example, the Li ion exchange battery exploits charge transfer of mixed Mn+3, Mn+4 materials. Charge localization and phase separation, especially at particle surfaces, are critical issues for determining the materials’ useful properties, be it catalytic activity or saturation magnetization. The ability to image the charge localization and correlate this with crystallographic information would be extremely useful in the study of this class of materials. Using energy-filtered transmission electron microscopy (EFTEM), valence maps of Mn and Co with a ∼ 2 nm scale have been obtained for bulk samples. In principal this technique can de directly extended to the case of particulate samples, however there are some additional experimental challenges, such as thickness and edge effects, that must be addressed. We demonstrate here the feasibility of valence mapping of particulate samples, and discuss the factors that limit quantitative data extraction from the maps.

APA, Harvard, Vancouver, ISO, and other styles

35

Wang, Zhikai, Xiangtao Lin, Taoyong Liu, Lidan Liu, Xingxing Jiang, Yanjun Yu, Tianxiang Ning, Anxian Lu, and Yong Jiang. "Thermal, chemical properties and structure evolution of medical neutral glasses modified by transition metal oxides." Journal of Non-Crystalline Solids 595 (November 2022): 121835. http://dx.doi.org/10.1016/j.jnoncrysol.2022.121835.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Zhao, Xingru, Qi An, and Jingwen Cai. "Recent Progress in the Transition Metal Sulfide/Phosphide for Cancer Theranostic Applications." Cancer Insight 1, no. 2 (December 22, 2022): 52–75. http://dx.doi.org/10.58567/ci01020005.

Full text

Abstract:

Transition metal sulfides/transition metal phosphides (TMS/TMP) has shown great potential in cancer diagnosis and treatment due to its unique structural, optical, acoustic and magnetic properties. TMS/TMP can be formed from sulfur/phosphorus source and metal into binary compounds, or from the interaction of hydrogen sulfide (or hydrogen sulfuric acid) with metal oxides or hydroxides. It has a series of unique properties, such as high conductivity, metalloid properties, a variety of valence states and adjustable structure and so on. These advantages make it have great potential in biomedical applications, such as diagnostic imaging, disease therapy and drug/gene delivery. This review presents the latest research progress of TMS/TMP on tumor imaging, diagnosis and treatment. Here, we first illustrate the synthesis approaches and surface modification of TMS/TMP. Then, its emerging applications in tumor diagnosis and therapy are highlighted. Moreover, the challenges of TMS/TMP-mediated diagnosis/treat are provided and the prospective for this field are discussed.

APA, Harvard, Vancouver, ISO, and other styles

37

Erkişi, Aytaç, Erdem Kamil Yıldırım, and Gökhan Gökoğlu. "Electronic structure and magnetic properties of PbMO3 (M = Fe, Co, Ni) magnetic perovskites: An ab initio study." International Journal of Modern Physics B 28, no. 29 (November 20, 2014): 1450205. http://dx.doi.org/10.1142/s0217979214502051.

Full text

Abstract:

We present the electronic, magnetic and structural properties of the magnetic transition metal oxides PbMO 3 (M = Fe , Co , Ni ) in cubic perovskite structure. The calculations are based on the density functional theory (DFT) within plane-wave pseudopotential method and local spin density approximation (LSDA) of the exchange-correlation functional. On-site Coulomb interaction is also included in calculations (LSDA+ U ). The systems are considered in ferromagnetic (FM) and G-type antiferromagnetic (G-AFM) order. FM structures are energetically more favored than G-AFM and than non-magnetic states for all the systems studied. The spin-polarized electronic band structures show that all the structures have metallic property in FM order without Hubbard-U interaction (U eff = 0). However, the inclusion of on-site Coulomb interaction (U eff = 7 eV ) opens a semiconducting gap for majority spin channel of PbFeO 3 and of PbNiO 3 resulting in a half-metallic character. PbCoO 3 system remains as metallic with LSDA+ U scheme. Bonding features of all structures are largely determined by the hybridizations between O–p and d-states of transition metal atoms. The partial magnetic moment of Fe atom in PbFeO 3 is enhanced by inclusion of Hubbard-U interaction (2.55 μB ⇒ 3.78 μB). Total magnetic moments of half-metallic PbFeO 3 and of PbNiO 3 compounds are very close to integer values.

APA, Harvard, Vancouver, ISO, and other styles

38

Cinthia, Arumainayagam Jemmy, Ratnavelu Rajeswarapalanichamy, and Kombiah Iyakutti. "First Principles Study of Electronic Structure, Magnetic, and Mechanical Properties of Transition Metal Monoxides TMO(TM=Co and Ni)." Zeitschrift für Naturforschung A 70, no. 10 (October 1, 2015): 797–804. http://dx.doi.org/10.1515/zna-2015-0216.

Full text

Abstract:

AbstractThe ground-state properties, electronic structure, magnetic and mechanical properties of cobalt oxide (CoO) and nickel oxide (NiO) are investigated using generalised gradient approximation parameterised by Perdew–Burke–Ernzerhof (GGA-PBE) and GGA-PBE+U formalisms. These oxides are found to be stable in the antiferromagnetic (AFM) state at normal pressure. The computed lattice parameters are in agreement with the experimental and other theoretical works. Pressure-induced magnetic transition from AFM to ferromagnetic (FM) state is predicted in NiO at a pressure of 84 GPa. Both these compounds are found to be mechanically stable in the AFM state at normal pressure.

APA, Harvard, Vancouver, ISO, and other styles

39

DEAC, I. G., A. VLĂDESCU, I. BALASZ, A. TUNYAGI, and R. TETEAN. "ELECTRICAL AND MAGNETIC BEHAVIOR OF TRANSITION METAL OXIDES Ln0.7A0.3TMO3, Ln= La, Pr; A = Ca, Sr AND TM = Mn, Co." International Journal of Modern Physics B 24, no. 06n07 (March 20, 2010): 762–69. http://dx.doi.org/10.1142/s0217979210064393.

Full text

Abstract:

We present a detailed magnetic study of the polycrystalline transition metal oxides Ln 0.7 A 0.3 TMO 3, Ln = La , Pr ; A = Ca , Sr and TM = Mn , Co at low temperatures including electrical resistance, magnetization and ac susceptibility measurements. The effect of the A-site and B-site substitutions on the properties of these compounds is discussed. The results of this analysis indicate that the electrical and magnetic behavior of these compounds have some reminiscences of the manganites having similar formula, but the spin disorder and the grain boundary effects control the properties of these materials.

APA, Harvard, Vancouver, ISO, and other styles

40

Becker, K. D. "Spectroscopicin situstudies of defect-dependent properties of transition metal oxides Defects, diffusion, and reaction kinetics." Philosophical Magazine A 68, no. 4 (October 1993): 767–86. http://dx.doi.org/10.1080/01418619308213996.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Salman, S. M., S. N. Salama, and Ebrahim A. Mahdy. "Contribution of some transition metal oxides to crystallization and electro-thermal properties of glass-ceramics." Ceramics International 46, no. 9 (June 2020): 13724–31. http://dx.doi.org/10.1016/j.ceramint.2020.02.160.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Ohtomo, Akira, Suvankar Chakraverty, Hisanori Mashiko, Takayoshi Oshima, and Masashi Kawasaki. "Spontaneous atomic ordering and magnetism in epitaxially stabilized double-perovskites." MRS Proceedings 1454 (2012): 3–13. http://dx.doi.org/10.1557/opl.2012.923.

Full text

Abstract:

ABSTRACTWe report on the atomic ordering of B-site transition-metals and magnetic properties in double-perovskite oxides, La2CrFeO6 (LCFO) and La2VMnO6 (LVMO), which have never been reported to exist in ordered forms. These double-perovskite oxides are particularly interesting because of possible ferromagnetism (expected from the Kanamori-Goodenough rule for LCFO) and half-metallic antiferromagnetism (predicted for LVMO). Using pulsed-laser deposition technique with single solid-solution targets, we have prepared epitaxial films in ordered forms. Despite similar ionic characters of constituent transition-metals in each compound, the maximum B-site order attained was surprisingly high, ∼90% for LCFO and ∼80% for LVMO, suggesting a significant role of epitaxial stabilization in the spontaneous ordering process. Magnetization and valence state characterizations revealed that the magnetic ground state of both compounds was coincidently ferrimagnetic with saturation magnetization of ∼2μBper formula unit, unlike those predicted theoretically. In addition, they were found to be insulating with optical band-gaps of 1.6 eV and 0.9 eV for LCFO and LVMO, respectively. Our results present a wide opportunity to explore novel magnetic properties of binary transition-metal perovskites upon epitaxial stabilization of the ordered phase.

APA, Harvard, Vancouver, ISO, and other styles

43

Chiromawa, Idris Muhammad, Amiruddin Shaari, Razif Razali, Summanuwa Timothy Ahams, and Mikailu Abdullahi. "Ab initio Investigation of the Structure and Electronic Properties of Normal Spinel Fe2SiO4." Malaysian Journal of Fundamental and Applied Sciences 17, no. 2 (April 29, 2021): 195–201. http://dx.doi.org/10.11113/mjfas.v17n2.2018.

Full text

Abstract:

Transition metal spinel oxides have recently been predicted to create efficient transparent conducting oxides for optoelectronic devices. These compounds can be easily tuned by doping or defect to adapt their electronic or magnetic properties. However, their cation distribution is very complex and band structures are still subject to controversy. We propose a complete density functional theory investigation of fayalite (Fe2SiO4) spinel, using Generalized Gradient Approximation (GGA) and Local Density Approximation (LDA) in order to explain the electronic and structural properties of this material. A detailed study of their crystal structure and electronic structure is given and compared with experimental data. The lattice parameters calculated are in agreement with the lattice obtained experimentally. The band structure of Fe2SiO4 spinel without Coulomb parameter U shows that the bands close to Fermi energy appear to be a band metal, with four iron d-bands crossing the Fermi level, in spite of the fact that from the experiment it is found to be an insulator.

APA, Harvard, Vancouver, ISO, and other styles

44

Nobile, Concetta, and Pantaleo Davide Cozzoli. "Synthetic Approaches to Colloidal Nanocrystal Heterostructures Based on Metal and Metal-Oxide Materials." Nanomaterials 12, no. 10 (May 18, 2022): 1729. http://dx.doi.org/10.3390/nano12101729.

Full text

Abstract:

Composite inorganic nanoarchitectures, based on combinations of distinct materials, represent advanced solid-state constructs, where coexistence and synergistic interactions among nonhomologous optical, magnetic, chemical, and catalytic properties lay a basis for the engineering of enhanced or even unconventional functionalities. Such systems thus hold relevance for both theoretical and applied nanotechnology-based research in diverse areas, spanning optics, electronics, energy management, (photo)catalysis, biomedicine, and environmental remediation. Wet-chemical colloidal synthetic techniques have now been refined to the point of allowing the fabrication of solution free-standing and easily processable multicomponent nanocrystals with sophisticated modular heterostructure, built upon a programmed spatial distribution of the crystal phase, composition, and anchored surface moieties. Such last-generation breeds of nanocrystals are thus composed of nanoscale domains of different materials, assembled controllably into core/shell or heteromer-type configurations through bonding epitaxial heterojunctions. This review offers a critical overview of achievements made in the design and synthetic elaboration of colloidal nanocrystal heterostructures based on diverse associations of transition metals (with emphasis on plasmonic metals) and transition-metal oxides. Synthetic strategies, all leveraging on the basic seed-mediated approach, are described and discussed with reference to the most credited mechanisms underpinning regioselective heteroepitaxial deposition. The unique properties and advanced applications allowed by such brand-new nanomaterials are also mentioned.

APA, Harvard, Vancouver, ISO, and other styles

45

GREENBLATT, MARTHA. "PHOSPHATE TUNGSTEN BRONZES — A NEW FAMILY OF QUASI-LOW-DIMENSIONAL METALLIC OXIDES." International Journal of Modern Physics B 07, no. 23n24 (October 30, 1993): 3937–71. http://dx.doi.org/10.1142/s0217979293003553.

Full text

Abstract:

A brief introduction is presented on transition metal oxide bronzes and their relationship to the phosphate tungsten bronzes; the latter compounds are the major focus of this review. The phosphate tungsten bronzes (PTB) are a new class of quasi-low-dimensional materials which exhibit charge density wave (CDW) instabilities. The growth of single crystals and investigation of the physical properties including the temperature dependence of the electrical resistivity and magnetic susceptibility on oriented single crystals are discussed for selected members of the major families in the PTB’s. Correlation of the physical measurement data with structural properties, X-ray diffraction data and results of the theoretical band structure calculations are also presented.

APA, Harvard, Vancouver, ISO, and other styles

46

Moshkina E. M., Molokeev M. S., Eremin E. V., and Bezmaternykh L. N. "Influence of Ga-substitution to the structural and magnetic properties of (Mn,Fe)-=SUB=-2-=/SUB=-O-=SUB=-3-=/SUB=- bixbyite." Physics of the Solid State 65, no. 6 (2023): 1009. http://dx.doi.org/10.21883/pss.2023.06.56116.57.

Full text

Abstract:

To study the dependence of the properties of ternary oxides (Mn,Fe,Ga)2O3 with the bixbyite structure on the composition, the temperature dependences of the magnetization and ac magnetic susceptibility of two single-crystal samples of different compositions obtained using the flux method were analyzed. A detailed study of the structure was carried out using single-crystal X-ray diffraction analysis, and the changes in structural parameters depending on the composition were analyzed. The dc magnetization and ac magnetic susceptibility of Fe1.1Mn0.76Ga0.14O3 and Fe0.65Mn1.1Ga0.26O3 bixbyites have been studied. Despite the qualitatively similar behavior of the magnetic properties, significant differences were also found, despite a small difference in the Mn/Fe/Ga ratio in the samples under study. It is shown that both compounds experience two successive low-temperature magnetic phase transitions from the paramagnetic phase at T=20-32 K as the temperature is lowered. Calculations of the Mydosh parameter for the detected phase transitions showed different degrees of ordering in the compounds under study. Keywords: transition metal oxides, magnetic phase transitions, spin glass state, bixbyite.

APA, Harvard, Vancouver, ISO, and other styles

47

Borchani, Sameh Megdiche, Wissem Cheikh-Rouhou Koubaa, and Makrem Megdiche. "Structural, magnetic and electrical properties of a new double-perovskite LaNaMnMoO 6 material." Royal Society Open Science 4, no. 11 (November 2017): 170920. http://dx.doi.org/10.1098/rsos.170920.

Full text

Abstract:

Structural, magnetic, magnetocaloric, electrical and magnetoresistance properties of an LaNaMnMoO 6 powder sample have been investigated by X-ray diffraction (XRD), magnetic and electrical measurements. Our sample has been synthesized using the ceramic method. Rietveld refinements of the XRD patterns show that our sample is single phase and it crystallizes in the orthorhombic structure with Pnma space group. Magnetization versus temperature in a magnetic applied field of 0.05 T shows that our sample exhibits a paramagnetic–ferromagnetic transition with decreasing temperature. The Curie temperature T C is found to be 320 K. Arrott plots show that all our double-perovskite oxides exhibit a second-order magnetic phase transition. From the measured magnetization data of an LaNaMnMoO 6 sample as a function of the magnetic applied field, the associated magnetic entropy change |−ΔSM| and the relative cooling power (RCP) have been determined. In the vicinity of T C , |−ΔSM| reached, in a magnetic applied field of 8 T, a maximum value of ∼4 J kg −1 K −1 . Our sample undergoes a large magnetocaloric effect at near-room temperature. Resistivity measurements reveal the presence of an insulating-metal transition at Tρ = 180 K. A magnetoresistance of 30% has been observed at room temperature for 6 T, significantly larger than that reported for the A 2 FeMoO 6 (A = Sr, Ba) double-perovskite system.

APA, Harvard, Vancouver, ISO, and other styles

48

Tsujimoto, Yoshihiro, Yoshitaka Matsushita, Kazunari Yamaura, and Tetsuo Uchikoshi. "High-pressure Synthesis of New layered Oxyhalide Perovskites." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C762. http://dx.doi.org/10.1107/s2053273314092377.

Full text

Abstract:

The development of transition metal oxides with perovskite-based structure has stimulated the search for mixed anion systems such as oxynitrides, oxyhalides and oxysulfides because incorporation of two different anions in one structure offers further opportunity to effectively induce chemical and physical properties that the pure oxides cannot possess. Such mixed anion phases, however, are difficult to be synthesized by a conventional high-temperature reaction. In this study, we have employed a high pressure technique to overcome this issue, and succeessfully synthesized a series of new layered oxhalide compounds. We present structural and magnetic properties of high-valent nickel oxyhalides Sr2NiO3X (X = F, Cl), and square-planar coordinated oxychlorides Sr2MO2Cl2 (Mn, Ni) and Ba2PdO2Cl2, isostructural with superconducting parent compund Ca2CuO2Cl2.

APA, Harvard, Vancouver, ISO, and other styles

49

Nocerino, Elisabetta, Ola K. Forslund, Chennan Wang, Hiroya Sakurai, Frank Elson, Rasmus Palm, Ugne Miniotaite, et al. "Magnetic nature of wolframite MgReO₄." Journal of Physics: Conference Series 2462, no. 1 (March 1, 2023): 012037. http://dx.doi.org/10.1088/1742-6596/2462/1/012037.

Full text

Abstract:

Abstract Rhenium oxides belonging to the family AReO4 where A is a metal cation, exhibit interesting electronic and magnetic properties. In this study we have utilized the muon spin rotation/relaxation (µ +SR) technique to study the magnetic properties of the MgReO4 compound. To the best of our knowledge, this is the first investigation reported on this interesting material, that is stabilized in a wolframite crystal structure using a special high-pressure synthesis technique. Bulk magnetic studies show the onset of an antiferromagnetic (AF) long range order, or a possible singlet spin state at T C1 ≈ 90 K, with a subtle second high-temperature transition at T C2 ≈ 280 K. Both transitions are also confirmed by heat capacity (Cp ) measurements. From our µ +SR measurements, it is clear that the sample enters an AF order below T C1 = T N ≈ 85 K. We find no evidence of magnetic signal above T N, which indicates that T C2 is likely linked to a structural transition. Further, via sensitive zero field (ZF) µ +SR measurements we find evidence of a spin reorientation at T Cant ≈ 65 K. This points towards a transition from a collinear AF into a canted AF order at low temperature, which is proposed to be driven by competing magnetic interactions.

APA, Harvard, Vancouver, ISO, and other styles

50

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.

Full text

Abstract:

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].

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Magnetic Properties - Exotic Transition Metal Oxides'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles