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Magnetic and orbital ordering in the spinel MnV2O4
1Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. garleao@ornl.gov
Physical Review Letters
|March 21, 2008
Summary
This study reveals two magnetic transitions in the MnV2O4 spinel system, leading to ordered ferrimagnetic states. A tetragonal distortion and excitation gap appear at lower temperatures, indicating staggered V orbital ordering.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- MnV2O4 is a spinel material exhibiting complex magnetic properties.
- Understanding its magnetic ordering and structural transitions is crucial for materials science.
Purpose of the Study:
- To investigate the magnetic transitions and low-temperature magnetic structure of the MnV2O4 spinel system.
- To elucidate the relationship between crystal structure, magnetic ordering, and electronic properties.
Main Methods:
- Neutron inelastic scattering and neutron diffraction techniques were employed.
- Detailed analysis of magnetic excitation spectra and crystal/magnetic structures.
Main Results:
- Two distinct transitions to long-range ordered ferrimagnetic states were observed.
- A lower-temperature transition involves antiferromagnetic components, tetragonal distortion, and a magnetic excitation gap.
- The low-temperature noncollinear magnetic structure was resolved, revealing staggered ordering of V d orbitals.
Conclusions:
- The observed phenomena are linked to the staggered ordering of V d orbitals.
- An anisotropy gap arises from unquenched V orbital angular momentum.
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