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Title: Estimation of dc transport dynamics in strongly correlated (La,Pr,Ca)MnO{sub 3} film using an insulator-metal composite model for terahertz conductivity

Abstract

Temperature-dependent conductivities at dc and terahertz (THz) frequency region (σ{sub THz}(ω,T)) were obtained for a strongly correlated (La{sub 0.275}Pr{sub 0.35}Ca{sub 0.375})MnO{sub 3} (LPCMO) film using THz time domain spectroscopy. A composite model that describes σ{sub THz}(ω,T) for LPCMO through the insulator-metal transition (IMT) was established by incorporating Austin-Mott model characterizing the hopping of localized electrons and Drude model explaining the behavior of free electrons. This model enables us to reliably investigate the dc transport dynamics from THz conductivity measurement, i.e., simultaneously evaluate the dc conductivity and the competing composition of metal and insulator phases through the IMT, reflecting the changes in microscopic conductivity of these phases.

Authors:
 [1];  [2]; ; ; ;  [1]; ;  [3]
  1. Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan)
  2. (Japan)
  3. Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531 (Japan)
Publication Date:
OSTI Identifier:
22311104
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 2; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CALCIUM COMPOUNDS; COMPOSITE MODELS; ELECTRIC CONDUCTIVITY; ELECTRONS; FILMS; LANTHANUM COMPOUNDS; MANGANATES; MANGANESE OXIDES; METALS; PRASEODYMIUM COMPOUNDS; SIMULATION; SPECTROSCOPY; TEMPERATURE DEPENDENCE; THZ RANGE

Citation Formats

Nguyen, T. V. A., Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Hattori, A. N., Nakamura, T., Fujiwara, K., Tanaka, H., E-mail: h-tanaka@sanken.osaka-u.ac.jp, Nagai, M., and Ashida, M. Estimation of dc transport dynamics in strongly correlated (La,Pr,Ca)MnO{sub 3} film using an insulator-metal composite model for terahertz conductivity. United States: N. p., 2014. Web. doi:10.1063/1.4890109.
Nguyen, T. V. A., Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Hattori, A. N., Nakamura, T., Fujiwara, K., Tanaka, H., E-mail: h-tanaka@sanken.osaka-u.ac.jp, Nagai, M., & Ashida, M. Estimation of dc transport dynamics in strongly correlated (La,Pr,Ca)MnO{sub 3} film using an insulator-metal composite model for terahertz conductivity. United States. doi:10.1063/1.4890109.
Nguyen, T. V. A., Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Hattori, A. N., Nakamura, T., Fujiwara, K., Tanaka, H., E-mail: h-tanaka@sanken.osaka-u.ac.jp, Nagai, M., and Ashida, M. Mon . "Estimation of dc transport dynamics in strongly correlated (La,Pr,Ca)MnO{sub 3} film using an insulator-metal composite model for terahertz conductivity". United States. doi:10.1063/1.4890109.
@article{osti_22311104,
title = {Estimation of dc transport dynamics in strongly correlated (La,Pr,Ca)MnO{sub 3} film using an insulator-metal composite model for terahertz conductivity},
author = {Nguyen, T. V. A. and Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531 and Hattori, A. N. and Nakamura, T. and Fujiwara, K. and Tanaka, H., E-mail: h-tanaka@sanken.osaka-u.ac.jp and Nagai, M. and Ashida, M.},
abstractNote = {Temperature-dependent conductivities at dc and terahertz (THz) frequency region (σ{sub THz}(ω,T)) were obtained for a strongly correlated (La{sub 0.275}Pr{sub 0.35}Ca{sub 0.375})MnO{sub 3} (LPCMO) film using THz time domain spectroscopy. A composite model that describes σ{sub THz}(ω,T) for LPCMO through the insulator-metal transition (IMT) was established by incorporating Austin-Mott model characterizing the hopping of localized electrons and Drude model explaining the behavior of free electrons. This model enables us to reliably investigate the dc transport dynamics from THz conductivity measurement, i.e., simultaneously evaluate the dc conductivity and the competing composition of metal and insulator phases through the IMT, reflecting the changes in microscopic conductivity of these phases.},
doi = {10.1063/1.4890109},
journal = {Applied Physics Letters},
number = 2,
volume = 105,
place = {United States},
year = {Mon Jul 14 00:00:00 EDT 2014},
month = {Mon Jul 14 00:00:00 EDT 2014}
}
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  • The doping of a manganese site with various M elements M=Fe{sup 3+}, Al{sup 3+}, Ga{sup 3+}, Ti{sup 4+}, Sn{sup 4+}, and Mg{sup 2+} was studied in insulating charge ordered manganite Pr{sub 0.6}Ca{sub 0.4}MnO{sub 3} that exhibits a canted CE-type magnetic structure. Whatever M, the charge ordering disappears for low x levels (x{ge}0.02) in doped manganite Pr{sub 0.6}Ca{sub 0.4}Mn{sub 1{minus}x}M{sub x}O{sub 3}. But the most important feature deals with the fact that a transition to a ferromagnetic metallic state is induced for M=Fe{sup 3+}, Al{sup 3+}, Ga{sup 3+}, and Mg{sup 2+} in spite of the small size of the interpolated cationmore » (Pr,Ca). In contrast, doping with a tetravalent cation does not drastically modify the magnetic and transport properties of the phase. {copyright} {ital 1997 American Institute of Physics.}« less
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