Structure and magnetism in LaCoO3.
D P Belanger1, T Keiber, F Bridges
1Department of Physics, University of California, Santa Cruz, CA 95064, USA.
Journal of Physics. Condensed Matter : an Institute of Physics Journal
|December 15, 2015
Summary
Researchers studied lanthanum cobaltate (LaCoO3) near its transition temperature. They observed unique changes in its crystal structure, which may explain its unusual magnetic properties.
Area of Science:
- Solid State Physics
- Materials Science
- Crystallography
Background:
- Lanthanum cobaltate (LaCoO3) exhibits complex magnetic and electronic properties.
- Understanding the relationship between crystal structure and magnetic behavior is crucial for materials science.
Purpose of the Study:
- To investigate the temperature dependence of the hexagonal lattice parameter c in LaCoO3.
- To correlate structural changes with the unusual magnetic behavior of LaCoO3.
Main Methods:
- High-resolution x-ray scattering was employed to measure the lattice parameter c.
- Measurements were conducted on single crystal and bulk powder LaCoO3 samples under varying magnetic fields (H = 0 and 800 Oe).
- The study focused on the temperature range near the transition temperature (T₀ ≈ 35 K).
Main Results:
- The temperature dependence of lattice parameter c, c(T), followed a power law for T > T₀.
- For T < T₀, c(T) became temperature-independent when convoluted with a Gaussian function (width 8.5 K).
- These structural changes were observed in both single crystal and bulk powder samples.
Conclusions:
- The observed temperature-dependent structural changes in LaCoO3 provide insights into its unique magnetic properties.
- The findings support the link between lattice dynamics and the anomalous magnetism in LaCoO3.
- Results are discussed in conjunction with theoretical calculations.
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