Magnetisation and Electron Spin Resonance of the colossal magnetoresistive La0.67Ca0.33Mn1-x FexO3
Sprache des Titels:
Englisch
Original Kurzfassung:
We report magnetisation and electron spin resonance (ESR) measurements on the colossal magnetoresistive
manganites La0.67Ca0.33Mn1–xFexO3, with x = 0, 0.01, 0.03, 0.06, 0.10, and 0.15, in the vicinity
of their magnetic (TC) and metal-insulator (TMI) transition temperatures. Above TC, the resonance lines
with g ≈ 2 are caused by ferromagnetic metallic clusters exhibiting a double exchange interaction between
Mn3+ – Mn4+ ions. The lines were observed with cooling far below both TC and TMI, and were fitted by
the Dysonian line-shape. The temperature dependences of the line-widths exhibited a minimum value at
Tmin ≈ 1.25TC, followed by an increase with further cooling toward TC. The anomalous behaviour of the
line-width below Tmin is due to the appearance of a ferromagnetic metallic phase within the paramagnetic
matrix. The role of phase segregation, in which the compounds are phase-separated into a mixture of
ferromagnetic and paramagnetic regions, is discussed.
Sprache der Kurzfassung:
Englisch
Englische Kurzfassung:
We report magnetisation and electron spin resonance (ESR) measurements on the colossal magnetoresistive
manganites La0.67Ca0.33Mn1–xFexO3, with x = 0, 0.01, 0.03, 0.06, 0.10, and 0.15, in the vicinity
of their magnetic (TC) and metal-insulator (TMI) transition temperatures. Above TC, the resonance lines
with g ≈ 2 are caused by ferromagnetic metallic clusters exhibiting a double exchange interaction between
Mn3+ – Mn4+ ions. The lines were observed with cooling far below both TC and TMI, and were fitted by
the Dysonian line-shape. The temperature dependences of the line-widths exhibited a minimum value at
Tmin ≈ 1.25TC, followed by an increase with further cooling toward TC. The anomalous behaviour of the
line-width below Tmin is due to the appearance of a ferromagnetic metallic phase within the paramagnetic
matrix. The role of phase segregation, in which the compounds are phase-separated into a mixture of
ferromagnetic and paramagnetic regions, is discussed.
Journal:
Materials Science Poland
Volume:
24
Seitenreferenz:
795 - 801
Erscheinungsjahr:
2006
ISSN:
2083-134X
Anzahl der Seiten:
7
Notiz zur Publikation:
Magnetisation and Electron Spin Resonance of the colossal magnetoresistive La0.67Ca0.33Mn1-x FexO3
Tomasz Zając, Lucyna Folcik, Janusz Chmist, Andrzej Kołodziejczyk, Henryk Drulis,
Karol Krop, Gerhard Gritzner
Materials Science Poland(Wroclaw University of Technology) 24 (2006) 795 - 801
Reichweite:
international
Publikationstyp:
Aufsatz / Paper in sonstiger referierter Fachzeitschrift
Forschungs-