Extrinsic and intrinsic features above TC in layered manganite: La1.2Sr1.8Mn2O7

N. O. Moreno; P. G. Pagliuso; C. Rettori; J. S. Gardner; J. L. Sarrao; J. D. Thompson; D. L. Huber; A. Garcia-Flores; S. B. Oseroff

doi:10.1016/S0921-4526(00)00496-8

Extrinsic and intrinsic features above T_C in layered manganite: La_1.2Sr_1.8Mn₂O₇

N. O. Moreno, P. G. Pagliuso, C. Rettori, J. S. Gardner, J. L. Sarrao, J. D. Thompson, D. L. Huber, A. Garcia-Flores, S. B. Oseroff

Research output: Contribution to journal › Article › peer-review

16 Scopus citations

Abstract

We have performed EPR and DC magnetization measurements on single crystals of La_1.2Sr_1.8Mn₂O₇. Similar to previous authors, we found an increase in the magnetization, M, near 300 K, a temperature well above T_C approx. 125 K. Previously, this high temperature (approx. 300 K) feature has been suggested to be intrinsic to the system. We have observed at these high temperatures the appearance of new ferromagnetic resonances, FMR. Within the experimental error the volume of sample required to explain the extra M and the intensity of the FMR is the same. We conclude that the increase in M and the FMR are due to the presence of extrinsic Ruddlesden-Popper (RP) phases and not to intrinsic effects as has been claimed. Furthermore, the resonance field of the EPR line due to the La_1.2Sr_1.8Mn₂O₇ phase presents a measurable temperature-dependent anisotropy up to approx. 450 K. The anisotropy is proportional to M, independent of the extrinsic RP phase content, and intrinsic to the system. We show that demagnetization effects can explain only part of the anisotropy. The role of short-range magnetic ordering in the observed intrinsic features cannot be disregarded, however.

Original language	English
Pages (from-to)	1-8
Number of pages	8
Journal	Physica B: Physics of Condensed Matter
Volume	292
Issue number	1-2
DOIs	https://doi.org/10.1016/S0921-4526(00)00496-8
State	Published - Oct 2 2000
Externally published	Yes

Funding

This work was supported by FAPESP Grant No. 95/4721-4, No. 97/03065-1, No. 97/11563-1 São Paulo-SP-Brazil, CAPES-Brazil, NSF-INT No. 9602829, and NSF-DMR No. 9705155. Work done at Los Alamos was conducted under the auspices of the U.S. DOE. We thank Dr. J.F. Mitchell for interesting and helpful discussions. J.S.G. thanks Dr. K. McClellan and J.M. Roper for assistance with the crystal growths. AGF thanks Ministerio de Educacion y Cultura of Spain.

Access to Document

10.1016/S0921-4526(00)00496-8

Cite this

@article{d06fbc2f78564a209604f6a03679aa0d,

title = "Extrinsic and intrinsic features above TC in layered manganite: La1.2Sr1.8Mn2O7",

abstract = "We have performed EPR and DC magnetization measurements on single crystals of La1.2Sr1.8Mn2O7. Similar to previous authors, we found an increase in the magnetization, M, near 300 K, a temperature well above TC approx. 125 K. Previously, this high temperature (approx. 300 K) feature has been suggested to be intrinsic to the system. We have observed at these high temperatures the appearance of new ferromagnetic resonances, FMR. Within the experimental error the volume of sample required to explain the extra M and the intensity of the FMR is the same. We conclude that the increase in M and the FMR are due to the presence of extrinsic Ruddlesden-Popper (RP) phases and not to intrinsic effects as has been claimed. Furthermore, the resonance field of the EPR line due to the La1.2Sr1.8Mn2O7 phase presents a measurable temperature-dependent anisotropy up to approx. 450 K. The anisotropy is proportional to M, independent of the extrinsic RP phase content, and intrinsic to the system. We show that demagnetization effects can explain only part of the anisotropy. The role of short-range magnetic ordering in the observed intrinsic features cannot be disregarded, however.",

author = "Moreno, {N. O.} and Pagliuso, {P. G.} and C. Rettori and Gardner, {J. S.} and Sarrao, {J. L.} and Thompson, {J. D.} and Huber, {D. L.} and A. Garcia-Flores and Oseroff, {S. B.}",

year = "2000",

month = oct,

day = "2",

doi = "10.1016/S0921-4526(00)00496-8",

language = "English",

volume = "292",

pages = "1--8",

journal = "Physica B: Physics of Condensed Matter",

issn = "0921-4526",

publisher = "Elsevier",

number = "1-2",

}

TY - JOUR

T1 - Extrinsic and intrinsic features above TC in layered manganite

T2 - La1.2Sr1.8Mn2O7

AU - Moreno, N. O.

AU - Pagliuso, P. G.

AU - Rettori, C.

AU - Gardner, J. S.

AU - Sarrao, J. L.

AU - Thompson, J. D.

AU - Huber, D. L.

AU - Garcia-Flores, A.

AU - Oseroff, S. B.

PY - 2000/10/2

Y1 - 2000/10/2

N2 - We have performed EPR and DC magnetization measurements on single crystals of La1.2Sr1.8Mn2O7. Similar to previous authors, we found an increase in the magnetization, M, near 300 K, a temperature well above TC approx. 125 K. Previously, this high temperature (approx. 300 K) feature has been suggested to be intrinsic to the system. We have observed at these high temperatures the appearance of new ferromagnetic resonances, FMR. Within the experimental error the volume of sample required to explain the extra M and the intensity of the FMR is the same. We conclude that the increase in M and the FMR are due to the presence of extrinsic Ruddlesden-Popper (RP) phases and not to intrinsic effects as has been claimed. Furthermore, the resonance field of the EPR line due to the La1.2Sr1.8Mn2O7 phase presents a measurable temperature-dependent anisotropy up to approx. 450 K. The anisotropy is proportional to M, independent of the extrinsic RP phase content, and intrinsic to the system. We show that demagnetization effects can explain only part of the anisotropy. The role of short-range magnetic ordering in the observed intrinsic features cannot be disregarded, however.

AB - We have performed EPR and DC magnetization measurements on single crystals of La1.2Sr1.8Mn2O7. Similar to previous authors, we found an increase in the magnetization, M, near 300 K, a temperature well above TC approx. 125 K. Previously, this high temperature (approx. 300 K) feature has been suggested to be intrinsic to the system. We have observed at these high temperatures the appearance of new ferromagnetic resonances, FMR. Within the experimental error the volume of sample required to explain the extra M and the intensity of the FMR is the same. We conclude that the increase in M and the FMR are due to the presence of extrinsic Ruddlesden-Popper (RP) phases and not to intrinsic effects as has been claimed. Furthermore, the resonance field of the EPR line due to the La1.2Sr1.8Mn2O7 phase presents a measurable temperature-dependent anisotropy up to approx. 450 K. The anisotropy is proportional to M, independent of the extrinsic RP phase content, and intrinsic to the system. We show that demagnetization effects can explain only part of the anisotropy. The role of short-range magnetic ordering in the observed intrinsic features cannot be disregarded, however.

UR - http://www.scopus.com/inward/record.url?scp=0034596686&partnerID=8YFLogxK

U2 - 10.1016/S0921-4526(00)00496-8

DO - 10.1016/S0921-4526(00)00496-8

M3 - Article

AN - SCOPUS:0034596686

SN - 0921-4526

VL - 292

SP - 1

EP - 8

JO - Physica B: Physics of Condensed Matter

JF - Physica B: Physics of Condensed Matter

IS - 1-2

ER -

Extrinsic and intrinsic features above T_C in layered manganite: La_1.2Sr_1.8Mn₂O₇

Abstract

Funding

Access to Document

Other files and links

Fingerprint

Cite this