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Iron spin-reorientation transition in NdFeAsO
A Marcinkova1, T C Hansen, J W G Bos
1School of Chemistry and Centre for Science at Extreme Conditions, University of Edinburgh, West Mains Road, Edinburgh, EH9 3JJ, UK.
Summary
Researchers studied the magnetic structure of Neodymium Iron Arsenide Oxide (NdFeAsO) using neutron powder diffraction. They found a complex interplay between rare-earth and transition metal magnetism, revealing a spin-reorientation in the iron sublattice.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- Neodymium Iron Arsenide Oxide (NdFeAsO) is a material exhibiting complex magnetic properties.
- Understanding its low-temperature magnetic structure is crucial for exploring its potential applications.
Purpose of the Study:
- To accurately determine the low-temperature magnetic structure of NdFeAsO.
- To investigate the magnetic interactions between rare-earth (Nd) and transition metal (Fe) sublattices.
Main Methods:
- Neutron powder diffraction was employed to probe the magnetic structure.
- Symmetry analysis using the Sarah representational analysis program was utilized for model testing.
Main Results:
- A model with Fe moments along the c-direction and Nd moments along the a-direction provided the best fit to the diffraction data.
- A significant interplay between Nd and Fe magnetism was observed, leading to spin-reorientation of the Fe sublattice.
- The determined Fe moment was 0.5 μ(B) and the Nd moment was 0.9 μ(B).
Conclusions:
- The magnetic ordering in NdFeAsO is characterized by a complex, non-collinear structure.
- The observed spin-reorientation highlights the strong coupling between rare-earth and transition metal magnetic sublattices.
- The low-temperature Fe moment is not significantly enhanced beyond the spin-density wave state.
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