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Sahu M, Ghosh B, Joseph B, Mishra AK, Mukherjee GD. High pressure ferroelectric-like semi-metallic state in Eu-doped BaTiO3. J Chem Phys 2024; 161:094202. [PMID: 39230368 DOI: 10.1063/5.0204542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 08/21/2024] [Indexed: 09/05/2024] Open
Abstract
We have conducted a detailed high-pressure (HP) investigation on Eu-doped BaTiO3 using angle-resolved x-ray diffraction, Raman spectroscopy, and dielectric permittivity measurements. The x-ray diffraction data analysis shows a pressure-induced structural phase transition from the ambient tetragonal to the mixed cubic and tetragonal phases above 1.4 GPa. The tetragonality of the sample due to the internal deformation of the TiO6 octahedra caused by the charge difference from Eu doping cannot be lifted by pressure. Softening, weakening, and disappearance of low-frequency Raman modes indicate ferroelectric tetragonal to the paraelectric cubic phase transition. However, the pressure-induced increase in the intensity of [E(LO), A1(LO)] and the octahedral breathing modes indicate that the local structural inhomogeneity remains in the crystal and is responsible for spontaneous polarization in the sample. The low-frequency electronic scattering response suggests pressure-induced carrier delocalization, leading to a semi-metallic state in the system. Our HP dielectric constant data can be explained by the presence of pressure-induced localized clusters of microscopic ferroelectric ordering. Our results suggest that the HP phase coexistence leads to a ferroelectric-like semi-metallic state in Eu-doped BaTiO3 under extreme quantum limits.
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Affiliation(s)
- Mrinmay Sahu
- National Centre for High Pressure Studies, Department of Physical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur Campus, Mohanpur, 741246 Nadia, West Bengal, India
| | - Bishnupada Ghosh
- National Centre for High Pressure Studies, Department of Physical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur Campus, Mohanpur, 741246 Nadia, West Bengal, India
| | - Boby Joseph
- Elettra-Sincrotrone Trieste, S. S. 14 km 163.5, 34149 Basovizza, Trieste, Italy
| | - Asish Kumar Mishra
- National Centre for High Pressure Studies, Department of Physical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur Campus, Mohanpur, 741246 Nadia, West Bengal, India
| | - Goutam Dev Mukherjee
- National Centre for High Pressure Studies, Department of Physical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur Campus, Mohanpur, 741246 Nadia, West Bengal, India
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Manh DH, Ngoc Nha TT, Hong Phong LT, Nam PH, Thanh TD, Phong PT. Determination of the crystalline size of hexagonal La 1-xSr xMnO 3 ( x = 0.3) nanoparticles from X-ray diffraction - a comparative study. RSC Adv 2023; 13:25007-25017. [PMID: 37614787 PMCID: PMC10443444 DOI: 10.1039/d3ra04018f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 08/16/2023] [Indexed: 08/25/2023] Open
Abstract
The electronic, magnetic, optical and elastic properties of nanomaterials are governed partially by the crystallite size and crystal defects. Here, the crystalline size of hexagonal La1-xSrxMnO3 (x = 0.3) nanoparticles was determined using various methods. Single-phase La0.7Sr0.3MnO3 nanopowders were produced after 10 h of milling in a commercial high-energy SPEX 8000D shaker mill, and then they were heated at 700 °C and 800 °C to study the effect of calcined temperature on the crystallization of nanoparticles. The modified Scherrer, Williamson-Hall, size-strain, and Halder-Wagner methods were used to determine the crystallite sizes and the elastic properties, such as intrinsic strain, stress, and energy density, from the X-ray diffraction peak broadening analysis. The obtained results were then compared with one another. The difference in crystallite sizes calculated from the different methods was due to the different techniques.
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Affiliation(s)
- Do Hung Manh
- Institute of Materials Science, Vietnam Academy of Science and Technology 18-Hoang Quoc Viet Hanoi City Vietnam
- Graduate University of Science and Technology, Vietnam Academy of Science and Technology 18-Hoang Quoc Viet Hanoi City Vietnam
| | - Tran Thi Ngoc Nha
- Graduate University of Science and Technology, Vietnam Academy of Science and Technology 18-Hoang Quoc Viet Hanoi City Vietnam
| | - Le Thi Hong Phong
- Institute of Materials Science, Vietnam Academy of Science and Technology 18-Hoang Quoc Viet Hanoi City Vietnam
| | - Pham Hong Nam
- Institute of Materials Science, Vietnam Academy of Science and Technology 18-Hoang Quoc Viet Hanoi City Vietnam
| | - Tran Dang Thanh
- Institute of Materials Science, Vietnam Academy of Science and Technology 18-Hoang Quoc Viet Hanoi City Vietnam
- Graduate University of Science and Technology, Vietnam Academy of Science and Technology 18-Hoang Quoc Viet Hanoi City Vietnam
| | - Pham Thanh Phong
- Laboratory of Magnetism and Magnetic Materials, Science and Technology Advanced Institute, Van Lang University Ho Chi Minh City Vietnam
- Faculty of Applied Technology, School of Technology, Van Lang University Ho Chi Minh City Vietnam
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Stanton R, Trivedi DJ. Pyrovskite: A software package for the high-throughput construction, analysis, and featurization of two- and three-dimensional perovskite systems. J Chem Phys 2023; 159:064803. [PMID: 37555613 DOI: 10.1063/5.0159407] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 07/24/2023] [Indexed: 08/10/2023] Open
Abstract
The increased computational and experimental interest in perovskite systems comprising novel phases and reduced dimensionality has greatly expanded the search space for this class of materials. In similar fields, unified frameworks exist for the procedural generation and subsequent analysis of these complex condensed matter systems. Given the relatively recent rise in popularity of these novel perovskite phases, such a framework is yet to be created. In this work, we introduce Pyrovskite, an open source software package, to aid in both the high-throughput and fine-grained generation, simulation, and subsequent analysis of this expanded family of perovskite systems. Additionally, we introduce a new descriptor for octahedral distortions in systems, including, but not limited to, perovskites. This descriptor quantifies diagonal displacements of the B-site cation in a BX6 octahedral coordination environment, which has been shown to contribute to increased Rashba-Dresselhaus splitting in perovskite systems.
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Affiliation(s)
- Robert Stanton
- Department of Physics, Clarkson University, Potsdam, New York 13699, USA
| | - Dhara J Trivedi
- Department of Physics, Clarkson University, Potsdam, New York 13699, USA
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Jia H, Zhou W, Nan H, Wang C, Qing Y, Luo F, Zhu D. Enhanced high temperature microwave absorption of La0.9Sr0.1MnO3/MgAl2O4 composite ceramics based on controllable electrical conductivity. Ann Ital Chir 2020. [DOI: 10.1016/j.jeurceramsoc.2020.01.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Feng Q, Jin F, Zhou H, Wang L, Meng W, Zhang K, Wang J, Zhang J, Hou Y, Lu Q, Wu W. Induced Formation of Structural Domain Walls and Their Confinement on Phase Dynamics in Strained Manganite Thin Films. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1805353. [PMID: 30370644 DOI: 10.1002/adma.201805353] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 09/23/2018] [Indexed: 06/08/2023]
Abstract
Domain walls (DWs) in strongly correlated materials have provided fertile ground for the discovery of exotic phenomena, and controlling the formation of DWs is still a challenge. Here, it is demonstrated that a new type of structural DW can be induced in a series of manganite thin films, which are engineered to achieve a robust charge-ordering insulating (COI) ground state by selecting various films and substrates. The monoclinic domains are somewhat irregular in shape, and the corresponding DWs, taking the shape of closed loops, are ferromagnetic and metallic (FMM) at low temperatures. Remarkably, the DWs exhibit little dependence on temperature or magnetic field, due to the structural origins of the domains. Additionally, using magnetic force microscopy, the role played by DWs in the dynamics of the COI and FMM phases at the mesoscopic scale is revealed. They function as barriers, strictly confining the phase dynamics within each domain, reflecting the strong coupling of electronic phases with the lattice. Each domain exhibits binary occupation by a single pure phase, resulting in a quasi-periodic phase separation. The universal behaviors of the multiple engineered films elucidate the possibility of controlling the formation of DWs and tuning phase dynamics through DW design.
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Affiliation(s)
- Qiyuan Feng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026, China
| | - Feng Jin
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026, China
| | - Haibiao Zhou
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026, China
| | - Lingfei Wang
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026, China
| | - Wenjie Meng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Kexuan Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026, China
| | - Jihao Wang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Jing Zhang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Yubin Hou
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Qingyou Lu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Wenbin Wu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230026, China
- Hefei Science Center, Chinese Academy of Sciences, Hefei, 230031, China
- Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, China
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Sadhu A, Salunke HG, Shivaprasad SM, Bhattacharyya S. Extensive Parallelism between Crystal Parameters and Magnetic Phase Transitions of Unusually Ferromagnetic Praseodymium Manganite Nanoparticles. Inorg Chem 2016; 55:7903-11. [PMID: 27482757 DOI: 10.1021/acs.inorgchem.6b00815] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The alterations in physical property across different space groups of the same material are sometimes conveniently reflected by the crystal structure as a function of temperature. However, mirroring the physical property and crystal parameters over a wide range of temperatures within the same space group is quite unusual. Remarkably, Rietveld analyses of the X-ray diffraction patterns of PrMn0.9O3 (ABO3) nanoparticles (NPs) with a constant Pnma space group from 300 to 10 K could successfully predict the four magnetic phases, viz. paramagnetic, antiferromagnetic (AFM), ferromagnetic (FM), and spin-glass-like ordering. The increase in Mn-O-Mn bond angles and tolerance factor leads to FM ordering below ∼100 K in usually AFM PrMn0.9O3 NPs. The concurrent decrease of lattice cell volume and Mn-O-Mn bond angles near the AFM to FM transition temperature (Tc) suggests that the AFM character increases just above Tc due to atomic deformations and reduced Mn-Mn separation. The predictions from crystal structure refinement were successfully verified from the cooling path of the temperature-dependent field-cooled magnetization measurements. A mechanism involving incoherent spin reversal due to competition between the neighboring spins undergoing antiparallel to parallel spin rotations was suggested. The structure-property parallelism was cross-checked with the A-site vacant Pr0.9MnO3.2 NPs.
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Affiliation(s)
- Anustup Sadhu
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) , Kolkata, Mohanpur 741246, India
| | - Hemant G Salunke
- Technical Physics Division, Bhabha Atomic Research Centre , Trombay, Mumbai 400085, India
| | - Sonnada M Shivaprasad
- International Centre for Materials Science & Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur, Bangalore 560064, India
| | - Sayan Bhattacharyya
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) , Kolkata, Mohanpur 741246, India
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Marini C, Noked O, Kantor I, Joseph B, Mathon O, Shuker R, Kennedy BJ, Pascarelli S, Sterer E. Nb K-edge x-ray absorption investigation of the pressure induced amorphization in A-site deficient double perovskite La1/3NbO3. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:045401. [PMID: 26742465 DOI: 10.1088/0953-8984/28/4/045401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Nb K-edge x-ray absorption spectroscopy is utilized to investigate the changes in the local structure of the A-site deficient double perovskite La1/3NbO3 which undergoes a pressure induced irreversible amorphization. EXAFS results show that with increasing pressure up to 7.5 GPa, the average Nb-O bond distance decreases in agreement with the expected compression and tilting of the NbO6 octahedra. On the contrary, above 7.5 GPa, the average Nb-O bond distance show a tendency to increase. Significant changes in the Nb K-edge XANES spectrum with evident low energy shift of the pre-peak and the absorption edge is found to happen in La1/3NbO3 above 6.3 GPa. These changes evidence a gradual reduction of the Nb cations from Nb(5+) towards Nb(4+) above 6.3 GPa. Such a valence change accompanied by the elongation of the average Nb-O bond distances in the octahedra, introduces repulsion forces between non-bonding adjacent oxygen anions in the unoccupied A-sites. Above a critical pressure, the Nb reduction mechanism can no longer be sustained by the changing local structure and amorphization occurs, apparently due to the build-up of local strain. EXAFS and XANES results indicate two distinct pressure regimes having different local and electronic response in the La1/3NbO3 system before the occurence of the pressure induced amorphization at ∼14.5 GPa.
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Affiliation(s)
- C Marini
- CELLS-ALBA, Carretera B.P. 1413, Cerdanyola del Valles 08290, Spain. European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, BP220, 38043 Grenoble Cedex, France
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8
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Nandy A, Roychowdhury A, Kar T, Das D, Pradhan SK. Effect of sodium doping on the microstructure, lattice distortion and magnetic properties of GdMnO3 tiny single crystals. RSC Adv 2016. [DOI: 10.1039/c5ra19631k] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
10% monovalent sodium doping reduces the octahedral and lattice distortion in GdMnO3 tiny single crystals and introduces ferromagnetic ordering in the compound.
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Affiliation(s)
- Anshuman Nandy
- Department of Physics
- The University of Burdwan
- Burdwan-713104
- India
| | - Anirban Roychowdhury
- UGC-DAE Consortium for Scientific Research
- Kolkata-700098
- India
- Department of Physics
- Krishnath College
| | - Tanushree Kar
- Indian Association for Cultivation of Science
- Kolkata-700032
- India
| | - Dipankar Das
- UGC-DAE Consortium for Scientific Research
- Kolkata-700098
- India
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9
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Islam MA, Xie Y, Scafetta MD, May SJ, Spanier JE. Raman scattering in La1-xSrxFeO3-δ thin films: annealing-induced reduction and phase transformation. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:155401. [PMID: 25812551 DOI: 10.1088/0953-8984/27/15/155401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Raman scattering in thin film La0.2Sr0.8FeO3-δ on MgO(0 0 1) collected at 300 K after different stages of annealing at selected temperatures T (300 K < T < 543 K, to 10 h) and analysis reveal changes in spectral characteristics due to a loss of oxygen, onset of oxygen vacancy-induced disorder, and activation of Raman-inactive modes that are attributed to symmetry lowering. The interpretation is further supported by carrier transport measurements under identical conditions showing orders of magnitude increase in the resistivity induced by oxygen loss. After prolonged annealing in air, evolution of the spectrum signals the appearance of a possible topotactic transformation of the crystal structure from that of the rhombohedral ABO3 perovskites to that of Brownmillerite-like structure consisting of octahedrally and tetrahedrally coordinated Fe atoms.
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Affiliation(s)
- Mohammad A Islam
- Department of Materials Science and Engineering, and the A J Drexel Institute for Energy and the Environment, Drexel University, Philadelphia, PA 19104, USA
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Vila-Fungueiriño JM, Rivas-Murias B, Rodríguez-González B, Txoperena O, Ciudad D, Hueso LE, Lazzari M, Rivadulla F. Room-temperature ferromagnetism in thin films of LaMnO3 deposited by a chemical method over large areas. ACS APPLIED MATERIALS & INTERFACES 2015; 7:5410-5414. [PMID: 25667996 DOI: 10.1021/am508941j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Hole-doping into the Mott insulator LaMnO3 results in a very rich magneto-electric phase diagram, including colossal magnetoresistance and different types of charge and orbital ordering. On the other hand, LaMnO3 presents an important catalytic activity for oxygen reduction, which is fundamental for increasing the efficiency of solid-oxide fuel cells and other energy-conversion devices. In this work, we report the chemical solution (water-based) synthesis of high-quality epitaxial thin films of LaMnO3, free of defects at square-centimeter scales, and compatible with standard microfabrication techniques. The films show a robust ferromagnetic moment and large magnetoresistance at room temperature. Through a comparison with films grown by pulsed laser deposition, we show that the quasi-equilibrium growth conditions characteristic of this chemical process can be exploited to tune new functionalities of the material.
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Affiliation(s)
- José Manuel Vila-Fungueiriño
- Centro de Investigación en Química Biológica y Materiales Moleculares (CIQUS), Universidad de Santiago de Compostela , 15782 Santiago de Compostela, Spain
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11
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Nandy A, Pradhan SK. Effects of monovalent cation doping on the structure, microstructure, lattice distortion and magnetic behavior of single crystalline NdMnO3compounds. Dalton Trans 2015; 44:17229-40. [PMID: 26373986 DOI: 10.1039/c5dt02154e] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
15% monovalent sodium and potassium doping reduces the structural distortion of NdMnO3with a subsequent modification in magnetic behavior.
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Affiliation(s)
- Anshuman Nandy
- Materials Science Division
- Department of Physics
- The University of Burdwan
- West Bengal-713104
- India
| | - S. K. Pradhan
- Materials Science Division
- Department of Physics
- The University of Burdwan
- West Bengal-713104
- India
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G Allodi G, De Renzi R, Zheng K, Sanna S, Sidorenko A, Baumann C, Righi L, Orlandi F, Calestani G. Band filling effect on polaron localization in La1-x(Ca(y)Sr1-y)xMnO3 manganites. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:266004. [PMID: 24912778 DOI: 10.1088/0953-8984/26/26/266004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report on a ìSR and 55 Mn NMR investigation of the magnetic order parameter as a function of temperature in the optimally doped La(5/8)(CaySr(1.y))(3/8)MnO3 and in the underdoped La1.xSrxMnO3 and La1.xCaxMnO3 metallic manganite families. The study is aimed at unravelling the effect of lattice distortions, implicitly controlled by the Ca-Sr isoelectronic substitution, from that of hole doping x on the Curie temperature TC and the order of the magnetic transition. At optimal doping, the transitions are second order at all y values, including the y = 1 (La(5/8)Ca(3/8)MnO3) end member. By contrast, they are first order in the underdoped samples, which show a finite (truncated) order parameter at the Curie point, including La(0.75)Sr(0.25)MnO3 whose TC is much higher than that of La(5/8)Ca(3/8)MnO3. The order parameter curves, on the other hand, exhibit a very minor dependence on x, if truncation is excepted. This suggests that the effective exchange interaction between Mn ions is essentially governed by local distortions, in agreement with the original double-exchange model, while truncation is primarily, if not entirely, an effect of under- or over-doping. A phase diagram, separating in the x.y plane polaron-driven first order transitions from regular second order transitions governed by critical fluctuations, is proposed for the La(1.x)(CaySr(1.y))xMnO3 system.
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Alejandro G, Otero-Leal M, Granada M, Laura-Ccahuana D, Tovar M, Winkler E, Causa MT. Phase coexistence in manganites: doping and structural dependence. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:256002. [PMID: 21393810 DOI: 10.1088/0953-8984/22/25/256002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We present a study on the phase coexistence (PC) of paramagnetic insulating (PM-I) and ferromagnetic metallic (FM-M) phases in the La(1- y)(Ca(1-x)Sr(x))(y)MnO(3) system with 0.23 ≤ y ≤ 0.45. The study was performed by means of magnetization and electron spin resonance (ESR) measurements. At high temperatures the ESR spectrum consists of a single symmetric PM line. At T(C), a FM asymmetric line is observed shifted to low fields. In a ΔT temperature range both lines are visible, defining a range of PC. For x = 0, we obtained ΔT as a function of the carrier concentration y, finding that the largest ΔT corresponds to y = 0.25. For this y value, the extreme compounds are orthorhombic and rhombohedral for x = 0 and 1, respectively. The rhombohedral to orthorhombic temperature transition (T(RO)) was determined as a function of x. We found that [Formula: see text] only if T(C) < T(RO). The PM-I/FM-M phase coexistence was only observed in the orthorhombic phase while seems to be incompatible with the more symmetric rhombohedral phase.
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Affiliation(s)
- G Alejandro
- Centro Atómico Bariloche, 8400 San Carlos de Bariloche, Río Negro, Argentina.
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Kitchen HJ, Saratovsky I, Hayward MA. Topotactic reduction as a synthetic route for the preparation of low-dimensional Mn(II) oxide phases: the structure and magnetism of LaAMnO(4-x) (A = Sr, Ba). Dalton Trans 2010; 39:6098-105. [PMID: 20571650 DOI: 10.1039/b923966a] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Reaction of LaSrMnO(4) with CaH(2) at 420 degrees C yields LaSrMnO(3.67(3)). Raising the temperature to 480 degrees C yields the Mn(II) phase LaSrMnO(3.50(2)). Neutron powder diffraction data show both phases adopt body-centred orthorhombic crystal structures (LaSrMnO(3.67(3)), Immm: a = 3.7256(1) A, b = 3.8227(1) A, c = 13.3617(4) A; LaSrMnO(3.50(2)), Immm: a = 3.7810(1) A, b = 3.7936(1) A, c = 13.3974(3) A) with anion vacancies located within the equatorial MnO(2-x) planes of the materials. Analogous reactivity is observed between LaBaMnO(4) and CaH(2) to yield body-centred tetragonal reduced phases (LaBaMnO(3.53(3)), I4/mmm: a = 3.8872(1)A, c = 13.6438(2) A). Low-temperature neutron diffraction and magnetisation data show that LaSrMnO(3.5) and LaBaMnO(3.5) exhibit three-dimensional antiferromagnetic order below 155 K and 135 K respectively. Above these temperatures, they exhibit two-dimensional antiferromagnetic order with paramagnetic behaviour observed above 480 K in both phases. The origin of the low dimensional magnetic order and ordering of the anion vacancies in the reduced phases is discussed.
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Affiliation(s)
- Helen J Kitchen
- Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QR
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15
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Malavasi L, Baldini M, di Castro D, Nucara A, Crichton W, Mezouar M, Blasco J, Postorino P. High pressure behavior of Ga-doped LaMnO3: a combined X-ray diffraction and optical spectroscopy study. ACTA ACUST UNITED AC 2010. [DOI: 10.1039/b914975a] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
Abstract
The assumption of perfect periodicity in the crystal lattice is the most basic tenet of crystallography. However, many materials are not crystalline. Even when they are the atomic structure of real materials is often less than perfectly periodic, and usually deviations from perfect periodicity have significant effects on their properties. Thus in order to characterize the structure of real materials by diffraction the crystallographic approaches need to be complemented by other methods focusing on disorder. B. E. Warren was a pioneer of such alternative, non-crystallographic approaches, including the method of atomic pair-density function (PDF) analysis. With the advent of synchrotron based radiation sources, such as pulsed neutron sources and synchrotron radiation sources, it recently became possible to apply the PDF technique on crystals with and without disorder, covering the whole spectrum of structural order and disorder. Here some of the recent progresses in this approach made in my research group are reviewed.
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Cheng YL, Dai JM, Zhu XB, Wu DJ, Yang ZR, Sun YP. Enhanced Microwave Absorption Properties of Intrinsically Core/shell Structured La(0.6)Sr(0.4)MnO(3) Nanoparticles. NANOSCALE RESEARCH LETTERS 2009; 4:1153-1158. [PMID: 20596374 PMCID: PMC2894104 DOI: 10.1007/s11671-009-9374-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2009] [Accepted: 06/04/2009] [Indexed: 05/15/2023]
Abstract
The intrinsically core/shell structured La(0.6)Sr(0.4)MnO(3) nanoparticles with amorphous shells and ferromagnetic cores have been prepared. The magnetic, dielectric and microwave absorption properties are investigated in the frequency range from 1 to 12 GHz. An optimal reflection loss of -41.1 dB is reached at 8.2 GHz with a matching thickness of 2.2 mm, the bandwidth with a reflection loss less than -10 dB is obtained in the 5.5-11.3 GHz range for absorber thicknesses of 1.5-2.5 mm. The excellent microwave absorption properties are a consequence of the better electromagnetic matching due to the existence of the protective amorphous shells, the ferromagnetic cores, as well as the particular core/shell microstructure. As a result, the La(0.6)Sr(0.4)MnO(3) nanoparticles with amorphous shells and ferromagnetic cores may become attractive candidates for the new types of electromagnetic wave absorption materials. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11671-009-9374-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- YL Cheng
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, 230031, Hefei, People’s Republic of China
| | - JM Dai
- School of Physics and Electronic Information, Huaibei Coal Industry Teachers College, 235000, Huaibei, People’s Republic of China
| | - XB Zhu
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, 230031, Hefei, People’s Republic of China
| | - DJ Wu
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, 230031, Hefei, People’s Republic of China
| | - ZR Yang
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, 230031, Hefei, People’s Republic of China
| | - YP Sun
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, 230031, Hefei, People’s Republic of China
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19
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Siwach PK, Singh HK, Srivastava ON. Low field magnetotransport in manganites. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2008; 20:273201. [PMID: 21694362 DOI: 10.1088/0953-8984/20/27/273201] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The perovskite manganites with generic formula RE(1-x)AE(x)MnO(3) (RE = rare earth, AE = Ca, Sr, Ba and Pb) have drawn considerable attention, especially following the discovery of colossal magnetoresistance (CMR). The most fundamental property of these materials is strong correlation between structure, transport and magnetic properties. They exhibit extraordinary large magnetoresistance named CMR in the vicinity of the insulator-metal/paramagnetic-ferromagnetic transition at relatively large applied magnetic fields. However, for applied aspects, occurrence of significant CMR at low applied magnetic fields would be required. This review consists of two sections: in the first section we have extensively reviewed the salient features, e.g. structure, phase diagram, double-exchange mechanism, Jahn-Teller effect, different types of ordering and phase separation of CMR manganites. The second is devoted to an overview of experimental results on CMR and related magnetotransport characteristics at low magnetic fields for various doped manganites having natural grain boundaries such as polycrystalline, nanocrystalline bulk and films, manganite-based composites and intrinsically layered manganites, and artificial grain boundaries such as bicrystal, step-edge and laser-patterned junctions. Some other potential magnetoresistive materials, e.g. pyrochlores, chalcogenides, ruthenates, diluted magnetic semiconductors, magnetic tunnel junctions, nanocontacts etc, are also briefly dealt with. The review concludes with an overview of grain-boundary-induced low field magnetotransport behavior and prospects for possible applications.
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Affiliation(s)
- P K Siwach
- Physics Department, Banaras Hindu University, Varanasi-221 005, India
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20
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Peña A, Gutiérrez J, Campo J, Barandiarán JM, Lezama L, Gil de Muro I, Rojo T. Structural, Magnetic and Magnetotransport Properties of La0.7Pb0.3(Mn1–xNix)O3 (0.1 ≤x ≤ 0.3) CMR Manganites. Eur J Inorg Chem 2008. [DOI: 10.1002/ejic.200701173] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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21
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Bozin ES, Schmidt M, Deconinck AJ, Paglia G, Mitchell JF, Chatterji T, Radaelli PG, Proffen T, Billinge SJL. Understanding the insulating phase in colossal magnetoresistance manganites: shortening of the Jahn-Teller long-bond across the phase diagram of La1-xCaxMnO3. PHYSICAL REVIEW LETTERS 2007; 98:137203. [PMID: 17501235 DOI: 10.1103/physrevlett.98.137203] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2006] [Indexed: 05/15/2023]
Abstract
The detailed evolution of the magnitude of the local Jahn-Teller (JT) distortion in La(1-x)Ca(x)MnO3 is obtained across the phase diagram for 0< or =x< or =0.5 from high-quality neutron diffraction data using the atomic pair distribution function method. A local JT distortion is observed in the insulating phase for all Ca concentrations studied. However, in contrast with earlier local structure studies, its magnitude is not constant, but decreases continuously with increasing Ca content. This observation is at odds with a simple small-polaron picture for the insulating state.
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Affiliation(s)
- E S Bozin
- Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824-2320, USA
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22
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Stinton GW, Evans JSO. Parametric Rietveld refinement. J Appl Crystallogr 2007; 40:87-95. [PMID: 19461841 PMCID: PMC2483475 DOI: 10.1107/s0021889806043275] [Citation(s) in RCA: 150] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Accepted: 10/17/2006] [Indexed: 11/10/2022] Open
Abstract
In this paper the method of parametric Rietveld refinement is described, in which an ensemble of diffraction data collected as a function of time, temperature, pressure or any other variable are fitted to a single evolving structural model. Parametric refinement offers a number of potential benefits over independent or sequential analysis. It can lead to higher precision of refined parameters, offers the possibility of applying physically realistic models during data analysis, allows the refinement of 'non-crystallographic' quantities such as temperature or rate constants directly from diffraction data, and can help avoid false minima.
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23
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Moshnyaga V, Sudheendra L, Lebedev OI, Köster SA, Gehrke K, Shapoval O, Belenchuk A, Damaschke B, van Tendeloo G, Samwer K. A-site ordering versus electronic inhomogeneity in colossally magnetoresistive manganite films. PHYSICAL REVIEW LETTERS 2006; 97:107205. [PMID: 17025850 DOI: 10.1103/physrevlett.97.107205] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2005] [Indexed: 05/12/2023]
Abstract
Epitaxial La(3/4)Ca(1/4)MnO3/MgO(100) (LCMO) thin film shows an unusual rhombohedral (R-3c) structure with a new perovskite superstructure at room temperature due to the CE-type ordering of La and Ca with modulation vector q=1/4[011]. A-site ordered film was found to be electronically homogeneous down to the 1 nm scale as revealed by scanning tunnelling microscopy/spectroscopy. In contrast, orthorhombic and A-site disordered LCMO demonstrate a mesoscopic phase separation far below the Curie temperature (TC). Unique La/Ca ordering compensates the cation mismatch stress within one supercell, a(S) approximately 1.55 nm, and enhances the electronic homogeneity. The phase separation does not seem to be a unique mechanism for the colossal magnetoresistance (CMR) as very large CMR approximately 500% was also observed in A-site ordered films.
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Affiliation(s)
- V Moshnyaga
- Erstes Physikalisches Institut, Universität Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen, Germany
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24
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Peña A, Gutiérrez J, de Muro IG, Campo J, Barandiarán JM, Rojo T. Correlation Between Structure and Magnetic and Magnetotransport Properties of La
0.7
Pb
0.3
(Mn
1 –
x
Co
x
)O
3
(0.1 ≤
x
≤ 0.3) CMR Manganites. Eur J Inorg Chem 2006. [DOI: 10.1002/ejic.200600104] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Alazne Peña
- Dpto. de Química Inorgánica, Fac. de Ciencia y Tecnología, Univ. del País Vasco/EHU, Apdo. 644, 48080 Bilbao, Spain
| | - Jon Gutiérrez
- Dpto. de Electricidad y Electrónica‐Un. As. CSIC, Fac. deCiencia y Tecnología, Univ. del País Vasco/EHU, Apdo. 644, 48080 Bilbao, Spain, Fax: +34‐94‐601‐3071
| | - Izaskun Gil de Muro
- Dpto. de Química Inorgánica, Fac. de Ciencia y Tecnología, Univ. del País Vasco/EHU, Apdo. 644, 48080 Bilbao, Spain
| | - Javier Campo
- Institut Laue Langevin (ILL, CRG‐D1B), Rue Jules Horowitz, B. P. 156, 38042 Grenoble Cedex 9, France
- New address: Instituto de Ciencia de los Materiales de Aragón, Universidad de Zaragoza, CSIC Facultad de Ciencias, 50009 Zaragoza, Spain
| | - Jose Manuel Barandiarán
- Dpto. de Electricidad y Electrónica‐Un. As. CSIC, Fac. deCiencia y Tecnología, Univ. del País Vasco/EHU, Apdo. 644, 48080 Bilbao, Spain, Fax: +34‐94‐601‐3071
| | - Teófilo Rojo
- Dpto. de Química Inorgánica, Fac. de Ciencia y Tecnología, Univ. del País Vasco/EHU, Apdo. 644, 48080 Bilbao, Spain
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Casey PS, Barker D, Hayward MA. Charge and structural ordering in the brownmillerite phases: La1−xSrxMnO2.5 (0.2 J SOLID STATE CHEM 2006. [DOI: 10.1016/j.jssc.2006.01.049] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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26
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Zheng G, Sun Y, Zhu X, Song W. Transport, magnetic, internal friction, and Young's modulus in the Y-doped manganites La0.9−xYxTe0.1MnO3. J SOLID STATE CHEM 2006. [DOI: 10.1016/j.jssc.2006.01.068] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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27
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Ghigna P, Carollo A, Flor G, Malavasi L, Peruga GS. Local Structure and Electronic Properties of the Rhombohedral and Orthorhombic Colossally Magnetoresistive Manganites La1-xNaxMnO3 by Mn−K Edge EXAFS and XANES. J Phys Chem B 2005; 109:4365-72. [PMID: 16851504 DOI: 10.1021/jp047751y] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The local structure and electronic properties of Mn in Na doped lanthanum manganites have been investigated by means of Mn-K edge XAFS, at various temperatures ranging from RT to 30 K. The hole content depends on the amount of doping, both with Na which injects two holes per doping atom and with oxygen nonstoichiometry. The holes are annihilated by oxygen under-stoichiometry via the formation of oxygen vacancies; the presence of a greater static disorder in the orthorhombic manganites is evidenced by both EXAFS and XANES analysis. In the rombohedral samples, a single Mn-O distance is found. In addition, the trend of the EXAFS Debye-Waller factors for the Mn-O distance can be fitted with a simple Einstein model, with no static disorder at low temperature. This evidence suggests small disorder of polaronic and of Jahn-Teller origin in the rombohedral samples at low temperatures, which is in contrast with what was found for the orthorhombic samples below T(c).
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Affiliation(s)
- Paolo Ghigna
- Dipartimento di Chimica Fisica M. Rolla, IENI/CNR and INSTM, Università di Pavia, V.le Taramelli 16, I-27100, Pavia, Italy
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28
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Influence of dopant concentration on the structure and physical properties of NdPbMnO single crystals. J SOLID STATE CHEM 2005. [DOI: 10.1016/j.jssc.2004.07.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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29
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Moshnyaga V, Damaschke B, Shapoval O, Belenchuk A, Faupel J, Lebedev OI, Verbeeck J, van Tendeloo G, Mücksch M, Tsurkan V, Tidecks R, Samwer K. Structural phase transition at the percolation threshold in epitaxial (La0.7Ca0.3MnO3)1-x:(MgO)x nanocomposite films. NATURE MATERIALS 2003; 2:247-252. [PMID: 12690398 DOI: 10.1038/nmat859] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2002] [Accepted: 02/18/2003] [Indexed: 05/24/2023]
Abstract
'Colossal magnetoresistance' in perovskite manganites such as La0.7Ca0.3MnO3 (LCMO), is caused by the interplay of ferro-paramagnetic, metal-insulator and structural phase transitions. Moreover, different electronic phases can coexist on a very fine scale resulting in percolative electron transport. Here we report on (LCMO)1-x:(MgO)x (0 < x < or = 0.8) epitaxial nano-composite films in which the structure and magnetotransport properties of the manganite nanoclusters can be tuned by the tensile stress originating from the MgO second phase. With increasing x, the lattice of LCMO was found to expand, yielding a bulk tensile strain. The largest colossal magnetoresistance of 10(5)% was observed at the percolation threshold in the conductivity at xc 0.3, which is coupled to a structural phase transition from orthorhombic (0 < x < or 0.1) to rhombohedral R3c structure (0.33 < or = x < or = 0.8). An increase of the Curie temperature for the Rc phase was observed. These results may provide a general method for controlling the magnetotransport properties of manganite-based composite films by appropriate choice of the second phase.
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Affiliation(s)
- V Moshnyaga
- I. Physikalisches Institut, Universität Göttingen, Bunsenstrasse 9, D-37073 Göttingen, Germany.
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31
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Ibarra-Palos A, Strobel P, Proux O, Hazemann J, Anne M, Morcrette M. In situ X-ray absorption spectroscopy study of lithium insertion in a new disordered manganese oxi-iodide. Electrochim Acta 2002. [DOI: 10.1016/s0013-4686(02)00236-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Mitchell JF, Argyriou DN, Berger A, Gray KE, Osborn R, Welp U. Spin, Charge, and Lattice States in Layered Magnetoresistive Oxides. J Phys Chem B 2001. [DOI: 10.1021/jp011419u] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J. F. Mitchell
- Materials Science Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439
| | - D. N. Argyriou
- Materials Science Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439
| | - A. Berger
- Materials Science Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439
| | - K. E. Gray
- Materials Science Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439
| | - R. Osborn
- Materials Science Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439
| | - U. Welp
- Materials Science Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439
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Congeduti A, Postorino P, Caramagno E, Nardone M, Kumar A, Sarma DD. Anomalous high pressure dependence of the Jahn-Teller phonon in La(0.75)Ca(0.25)MnO(3). PHYSICAL REVIEW LETTERS 2001; 86:1251-1254. [PMID: 11178056 DOI: 10.1103/physrevlett.86.1251] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2000] [Indexed: 05/23/2023]
Abstract
Raman spectra of La(0.75)Ca(0.25)MnO(3) have been collected for the first time over a wide pressure range (0-14 GPa) using a diamond anvil cell. The frequency range explored (200-1100 cm(-1)) and the very good quality of the data allowed us to carefully analyze the pressure evolution of the phonon modes of the MnO(6) octahedra. The results show an abrupt transition at approximately 7.5 GPa with an evident deviation from the linear trend of the frequency of the Jahn-Teller phonon versus the applied pressure, accompanied by a strong phonon broadening. This behavior disagrees with the predicted insulator to metal transition and, on the contrary, indicates the occurrence of a new unpredicted phase in the very high pressure regime.
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Affiliation(s)
- A Congeduti
- Dipartimento di Fisica, Universita di Roma "La Sapienza," Unita dell-Istituto Nazionale per la Fisica della Materia Piazzale Aldo Moro 2, 00185 Roma, Italy
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Zhang N, Yang W, Li G, Ding W, Xing D, Du Y. Sintering temperature-dependent magnetism and structure in granular perovskites La1−Sr MnO. Chem Phys Lett 1999. [DOI: 10.1016/s0009-2614(99)00925-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Brunelli M, Lanzara A, Saini NL, Bianconi A, Valletta A, Radaelli PG. Anomalous Jahn-Teller distortions in La0.75Ca0.25MnO3 system: An X-ray absorption study. ACTA ACUST UNITED AC 1997. [DOI: 10.1007/bf02765710] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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