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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Phase coexistence in manganites: doping and structural dependence
G Alejandro1, M Otero-Leal, M Granada
1Centro Atómico Bariloche, 8400 San Carlos de Bariloche, Río Negro, Argentina. galejand@cab.cnea.gov.ar
Summary
This study investigates phase coexistence in La(1-y)(Ca(1-x)Sr(x))(y)MnO(3) using magnetization and ESR. Phase coexistence was observed in the orthorhombic phase, but not the rhombohedral phase.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Solid State Chemistry
Background:
- The La(1-y)(Ca(1-x)Sr(x))(y)MnO(3) system exhibits complex phase behavior.
- Understanding phase coexistence is crucial for tuning material properties.
Purpose of the Study:
- To investigate the phase coexistence (PC) of paramagnetic insulating (PM-I) and ferromagnetic metallic (FM-M) phases.
- To determine the conditions under which PM-I/FM-M phase coexistence occurs in the La(1-y)(Ca(1-x)Sr(x))(y)MnO(3) system.
Main Methods:
- Magnetization measurements.
- Electron spin resonance (ESR) spectroscopy.
- Analysis of temperature-dependent phase transitions.
Main Results:
- A temperature range (ΔT) for phase coexistence was identified, where both paramagnetic and ferromagnetic signals were observed.
- The largest ΔT was found at a carrier concentration of y = 0.25 for x = 0.
- Phase coexistence was exclusively observed in the orthorhombic crystal phase, not the rhombohedral phase.
Conclusions:
- Phase coexistence of paramagnetic insulating and ferromagnetic metallic states is dependent on the crystal structure.
- The orthorhombic phase facilitates PM-I/FM-M phase coexistence, while the rhombohedral phase does not.
- The relationship between the ferromagnetic transition temperature (T(C)) and the rhombohedral-to-orthorhombic transition temperature (T(RO)) influences phase behavior.
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