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Title: Role of epitaxy and polycrystallinity in the magnetoresistance and magnetization of La{sub 0.8}Sr{sub 0.2}MnO{sub 3} thin films

Abstract

La{sub 0.8}Sr{sub 0.2}MnO{sub 3} thin films were simultaneously deposited by pulsed laser ablation on silicon (Si) and LaAlO{sub 3} (LAO) substrates. Films on Si were polycrystalline while those on LAO were (100) epitaxial with an in-plane correlation length of {approx_equal}10 nm. The magnetization and magnetoresistance behavior of these two films were significantly different. Both films exhibit antiferromagnetic{endash}ferromagnetic transitions{emdash}at different temperatures [180 K (LAO); 230 K (Si)]{emdash}and their magnetic moments at 10 K were significantly different (Si{emdash}0.0035 emu; LAO{emdash}0.0022 emu). However, both films showed significant high field slope in magnetization at 10 K. Significant fractions of both films remain antiferromagnetic at low temperatures and hence net susceptibilities, dependent on the direction of the applied magnetic field, are different for the epitaxial (LAO) and randomly oriented polycrystalline (Si) films. The magnetoresistance peak, corresponding to the semiconductor{endash}metal transition is observed at 170 and 130 K for the epitaxial (LAO) and polycrystalline (Si) films, respectively. Moreover, their resistance values are two orders of magnitude different (Si{emdash}MO/hms; LAO{emdash}KOhms). These properties can be interpreted in terms of the major role of grain boundaries in determining the scattering as well as possible differences in O{sub 2} stoichiometry. {copyright} {ital 1996 American Institute of Physics.}

Authors:
; ;  [1];  [2];  [3]
  1. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)
  2. Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)
  3. Materials Science and Mineral Engineering, University of California, Berkeley, California 94720 (United States)
Publication Date:
OSTI Identifier:
280036
Report Number(s):
CONF-951101-
Journal ID: JAPIAU; ISSN 0021-8979; TRN: 96:018950
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 79; Journal Issue: 8; Conference: 40. conference on magnetism and magnetic materials, Philadelphia, PA (United States), 6-9 Nov 1995; Other Information: PBD: Apr 1996
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; LANTHANUM OXIDES; MAGNETORESISTANCE; STRONTIUM OXIDES; MANGANESE OXIDES; POLYCRYSTALS; THIN FILMS; MAGNETIC MATERIALS; ENERGY BEAM DEPOSITION; LASER RADIATION; EPITAXY; SUBSTRATES; SILICON; ALUMINIUM OXIDES; MAGNETIZATION; PHASE TRANSFORMATIONS; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0000-0013 K; TEMPERATURE RANGE 0013-0065 K

Citation Formats

Krishnan, K.M., Modak, A.R., Lucas, C.A., Michel, R., and Cherry, H.B. Role of epitaxy and polycrystallinity in the magnetoresistance and magnetization of La{sub 0.8}Sr{sub 0.2}MnO{sub 3} thin films. United States: N. p., 1996. Web. doi:10.1063/1.361919.
Krishnan, K.M., Modak, A.R., Lucas, C.A., Michel, R., & Cherry, H.B. Role of epitaxy and polycrystallinity in the magnetoresistance and magnetization of La{sub 0.8}Sr{sub 0.2}MnO{sub 3} thin films. United States. doi:10.1063/1.361919.
Krishnan, K.M., Modak, A.R., Lucas, C.A., Michel, R., and Cherry, H.B. Mon . "Role of epitaxy and polycrystallinity in the magnetoresistance and magnetization of La{sub 0.8}Sr{sub 0.2}MnO{sub 3} thin films". United States. doi:10.1063/1.361919.
@article{osti_280036,
title = {Role of epitaxy and polycrystallinity in the magnetoresistance and magnetization of La{sub 0.8}Sr{sub 0.2}MnO{sub 3} thin films},
author = {Krishnan, K.M. and Modak, A.R. and Lucas, C.A. and Michel, R. and Cherry, H.B.},
abstractNote = {La{sub 0.8}Sr{sub 0.2}MnO{sub 3} thin films were simultaneously deposited by pulsed laser ablation on silicon (Si) and LaAlO{sub 3} (LAO) substrates. Films on Si were polycrystalline while those on LAO were (100) epitaxial with an in-plane correlation length of {approx_equal}10 nm. The magnetization and magnetoresistance behavior of these two films were significantly different. Both films exhibit antiferromagnetic{endash}ferromagnetic transitions{emdash}at different temperatures [180 K (LAO); 230 K (Si)]{emdash}and their magnetic moments at 10 K were significantly different (Si{emdash}0.0035 emu; LAO{emdash}0.0022 emu). However, both films showed significant high field slope in magnetization at 10 K. Significant fractions of both films remain antiferromagnetic at low temperatures and hence net susceptibilities, dependent on the direction of the applied magnetic field, are different for the epitaxial (LAO) and randomly oriented polycrystalline (Si) films. The magnetoresistance peak, corresponding to the semiconductor{endash}metal transition is observed at 170 and 130 K for the epitaxial (LAO) and polycrystalline (Si) films, respectively. Moreover, their resistance values are two orders of magnitude different (Si{emdash}MO/hms; LAO{emdash}KOhms). These properties can be interpreted in terms of the major role of grain boundaries in determining the scattering as well as possible differences in O{sub 2} stoichiometry. {copyright} {ital 1996 American Institute of Physics.}},
doi = {10.1063/1.361919},
journal = {Journal of Applied Physics},
number = 8,
volume = 79,
place = {United States},
year = {Mon Apr 01 00:00:00 EST 1996},
month = {Mon Apr 01 00:00:00 EST 1996}
}