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Title: Structural and magnetotransport properties of the Y doped A-site deficient double layered manganites La{sub 1.2−x}□{sub 0.2}Y{sub x}Ca{sub 1.6}Mn{sub 2}O{sub 7}

Abstract

We present structural, magnetic and electrical properties of the polycrystalline A-site-deficient yttrium doped double layered manganites La{sub 1.2−x}□{sub 0.2}Y{sub x}Ca{sub 1.6}Mn{sub 2}O{sub 7} (x=0.2, 0.3 and 0.4) prepared by a solid state reaction method. The samples crystallize in the tetragonal structure with the space group I4/mmm. Doping with Y decreases the cell parameters and causes a decrease of the metal-insulator transition temperature. The same evolution with doping is also seen for the deduced Curie temperature from susceptibility curves which present a clear paramagnetic-ferromagnetic transition. The significant positive intrinsic magnetoresistance, shown in all samples, reaches 85% at 122 K under 7 T for 0.3 doped sample and can be attributed to the suppression of spin fluctuations via aligning the spins under external magnetic field, while the extrinsic one is attributed to the inter-grain spin-polarized tunneling across the grain boundaries. The simulation of the resistivity curves in the entire temperature range show that the percolation model is suitable to fit our results. The applied magnetic field increases the density of states near the Fermi level, which is in accordance with the observed decrease of resistivity. - Graphical abstract: Resistivity and magnetoresistance of La{sub 1.2−x}□{sub 0.2}Y{sub x}Ca{sub 1.6}Mn{sub 2}O{sub 7} (x=0.2, 0.3, 0.4).more » Solid lines correspond to the fitting results. Display Omitted.« less

Authors:
 [1];  [1];  [2];  [3]; ;  [2]
  1. LEND, Faculty of Science and Technology, Jijel University, Jijel 18000 (Algeria)
  2. Department of Physics, Faculty of Arts and Sciences, AIB University, Bolu 14280 (Turkey)
  3. (KUYTAM), 34450-Sariyer, Istanbul (Turkey)
Publication Date:
OSTI Identifier:
22584171
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 240; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CURIE POINT; DENSITY; DENSITY OF STATES; DOPED MATERIALS; FERMI LEVEL; GRAIN BOUNDARIES; MAGNETIC FIELDS; MAGNETIC SUSCEPTIBILITY; MAGNETORESISTANCE; PARAMAGNETISM; PHASE TRANSFORMATIONS; POLYCRYSTALS; SIMULATION; SOLIDS; SPACE GROUPS; SPIN; SPIN ORIENTATION; TETRAGONAL LATTICES; TUNNEL EFFECT; YTTRIUM

Citation Formats

Mahamdioua, N., E-mail: mahamdioua.nabil@gmail.com, Amira, A., Altintas, S.P., Koc University, Surface Science and Technology Center, Varilci, A., and Terzioglu, C. Structural and magnetotransport properties of the Y doped A-site deficient double layered manganites La{sub 1.2−x}□{sub 0.2}Y{sub x}Ca{sub 1.6}Mn{sub 2}O{sub 7}. United States: N. p., 2016. Web. doi:10.1016/J.JSSC.2016.05.011.
Mahamdioua, N., E-mail: mahamdioua.nabil@gmail.com, Amira, A., Altintas, S.P., Koc University, Surface Science and Technology Center, Varilci, A., & Terzioglu, C. Structural and magnetotransport properties of the Y doped A-site deficient double layered manganites La{sub 1.2−x}□{sub 0.2}Y{sub x}Ca{sub 1.6}Mn{sub 2}O{sub 7}. United States. doi:10.1016/J.JSSC.2016.05.011.
Mahamdioua, N., E-mail: mahamdioua.nabil@gmail.com, Amira, A., Altintas, S.P., Koc University, Surface Science and Technology Center, Varilci, A., and Terzioglu, C. 2016. "Structural and magnetotransport properties of the Y doped A-site deficient double layered manganites La{sub 1.2−x}□{sub 0.2}Y{sub x}Ca{sub 1.6}Mn{sub 2}O{sub 7}". United States. doi:10.1016/J.JSSC.2016.05.011.
@article{osti_22584171,
title = {Structural and magnetotransport properties of the Y doped A-site deficient double layered manganites La{sub 1.2−x}□{sub 0.2}Y{sub x}Ca{sub 1.6}Mn{sub 2}O{sub 7}},
author = {Mahamdioua, N., E-mail: mahamdioua.nabil@gmail.com and Amira, A. and Altintas, S.P. and Koc University, Surface Science and Technology Center and Varilci, A. and Terzioglu, C.},
abstractNote = {We present structural, magnetic and electrical properties of the polycrystalline A-site-deficient yttrium doped double layered manganites La{sub 1.2−x}□{sub 0.2}Y{sub x}Ca{sub 1.6}Mn{sub 2}O{sub 7} (x=0.2, 0.3 and 0.4) prepared by a solid state reaction method. The samples crystallize in the tetragonal structure with the space group I4/mmm. Doping with Y decreases the cell parameters and causes a decrease of the metal-insulator transition temperature. The same evolution with doping is also seen for the deduced Curie temperature from susceptibility curves which present a clear paramagnetic-ferromagnetic transition. The significant positive intrinsic magnetoresistance, shown in all samples, reaches 85% at 122 K under 7 T for 0.3 doped sample and can be attributed to the suppression of spin fluctuations via aligning the spins under external magnetic field, while the extrinsic one is attributed to the inter-grain spin-polarized tunneling across the grain boundaries. The simulation of the resistivity curves in the entire temperature range show that the percolation model is suitable to fit our results. The applied magnetic field increases the density of states near the Fermi level, which is in accordance with the observed decrease of resistivity. - Graphical abstract: Resistivity and magnetoresistance of La{sub 1.2−x}□{sub 0.2}Y{sub x}Ca{sub 1.6}Mn{sub 2}O{sub 7} (x=0.2, 0.3, 0.4). Solid lines correspond to the fitting results. Display Omitted.},
doi = {10.1016/J.JSSC.2016.05.011},
journal = {Journal of Solid State Chemistry},
number = ,
volume = 240,
place = {United States},
year = 2016,
month = 8
}
  • The exploration of the Mn{sup 4+}-rich side of the Pr{sub 1{minus}x}Sr{sub x}MnO{sub 3} system has allowed the extension of the domain of the cubic perovskite, by using a two-step process, combining synthesis under Ar flow at high temperature and O{sub 2} pressure annealing at lower temperature. The authors show that these Pr-doped cubic perovskites exhibit a coupled structural (cubic-tetragonal) and magnetic (para-antiferro) transition connected with a resistivity jump at the same temperature. The strong interplay between lattice, charges, and spins for these oxides results from the appearance at low temperature of the distorted C-type antiferromagnetic structure. The Pr{sub 1{minus}x}Sr{sub x}MnO{submore » 3} magnetic phase diagram shows, for 0.9 {le} x < 1 (i.e., on the Mn{sup 4+}-rich side), the existence at low temperature of C- and G-type antiferromagnetism. The absence of ferromagnetic-antiferromagnetic competition explains that magnetoresistance properties are not observed in this system, in contrast to Mn{sup 4+}-rich Ln{sub 1{minus}x}Ca{sub x}MnO{sub 3} systems.« less
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  • We have prepared the polycrystalline samples of compositions YMn{sub 1+x}O{sub 3} (x =0, 0.17) and studied their structural properties using x-ray diffraction and Raman spectroscopy measurements. The sample with composition Y:Mn = 1:1 showed the antiferromagnetic transition in the magnetization verses temperature (M-T) measurements near 70 K similar to standard YMnO{sub 3}. But the sample with composition Y:Mn = 1:1.17 showed glass like magnetic transition around 42 K in the M-T measurements. Also, a hysteresis in the isothermal magnetization curve at 2K was observed for the Mn rich sample, while the linear trend of magnetization with magnetic field was noted for themore » sample with equal Y/Mn ratio at 2K. We understood that the Mn excess in Mn rich sample results in the formation of Mn{sup 2+} ions and the magnetic exchange among the Mn{sup 3+/}Mn{sup 2+} ions is responsible for the observed magnetic behaviour. The room temperature ferroelectric properties of the studied samples were also investigated by measuring P-E loops.« less
  • AMn{sub 1-x}Fe{sub x}O{sub 3} (A = La{sub 0.75}Ca{sub 0.08}Sr{sub 0.17} and x = 0-0.23) compounds, sintered at 700 deg. C, were characterized by X-ray diffraction (XRD) at room temperature. Rietveld refinement has shown that samples can be indexed in the orthorhombic (Pnma) structure for low Fe-content (x {<=} 0.046) and rhombohedral (R-3c) structure for high Fe-content (x {>=} 0.115). The transmission Moessbauer spectra have revealed the same isomer shift {delta} value assigned to Fe{sup 3+} ion for all compounds. The magnetization behavior and the Curie temperature T{sub C} have shown a large dependence on the fractional composition x. In fact,more » the M(T) curves have revealed the presence of a long-range ferromagnetic state below T{sub C} for compounds with x {<=} 0.115, and a spin-glass state (SGS) at low temperature for high Fe-content (x {>=} 0.177). Research Highlights: {yields} La{sub 0.75}Ca{sub 0.08}Sr{sub 0.17}Mn{sub 1-x}Fe{sub x}O{sub 3} compounds undergo a transition ortho-rhombo at x=0.046. {yields} On the rhombohedral phase, the magnetization is governed by the DE interaction {yields} The magnetization undergoes a strong decrease at high x-values (x{>=}0.115). {yields} Compounds show a strong AFM interaction with a spin-glass state at high Fe-content {yields} Hysteresis loops, M(H) confirm this behavior.« less
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