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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
Observation of a griffiths phase in paramagnetic La1-xSrxMnO3
J Deisenhofer1, D Braak, H-A Krug von Nidda
1EP V, Center for Electronic Correlations and Magnetism, University of Augsburg, 86135 Augsburg, Germany.
Physical Review Letters
|December 31, 2005
Summary
Researchers discovered a new triangular phase in La1-xSrxMnO3, showing ferromagnetic clusters above the ordering temperature. This phenomenon is explained by Griffiths singularities linked to quenched disorder.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Magnetism
Background:
- La1-xSrxMnO3 exhibits complex magnetic behaviors.
- Understanding phase transitions in disordered magnetic systems is crucial.
Purpose of the Study:
- To investigate a novel phase regime in La1-xSrxMnO3.
- To characterize the coexistence of ferromagnetic and paramagnetic states.
Main Methods:
- Electron spin resonance (ESR) spectroscopy.
- Magnetic susceptibility measurements.
Main Results:
- Discovery of a unique triangular phase regime.
- Observed coexistence of ferromagnetic entities in a paramagnetic phase well above the magnetic ordering temperature.
- Correlated quenched disorder in the orthorhombic phase was identified as the cause.
Conclusions:
- The discovered phase is attributed to Griffiths singularities.
- Correlated quenched disorder plays a significant role in the magnetic properties of La1-xSrxMnO3.
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