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Dispersive crystal field excitations and quadrupolar interactions in UPd3
1Helmholtz-Zentrum Berlin, Berlin, Germany. duc.le@helmholtz-berlin.de
Journal of Physics. Condensed Matter : an Institute of Physics Journal
|December 14, 2011
Summary
We measured crystal field excitations in UPd(3) using neutron scattering and calculations. Results match predictions, revealing anisotropic exchange parameters from hexagonal sites.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Understanding crystal field excitations is crucial for predicting magnetic properties of materials.
- Uranium compounds like UPd(3) exhibit complex electronic behaviors due to localized f-electrons.
Purpose of the Study:
- To investigate the dispersive crystal field excitations in UPd(3) using inelastic neutron scattering.
- To compare experimental results with theoretical calculations based on the random phase approximation.
- To determine quadrupolar and exchange interaction parameters.
Main Methods:
- Inelastic neutron scattering (INS) measurements were performed to probe crystal field excitations.
- Random phase approximation (RPA) calculations were employed for theoretical analysis.
- Data analysis involved deducing interaction parameters from spectral features.
Main Results:
- Experimental spectra at lower energies showed good agreement with RPA calculations.
- Quadrupolar interaction parameters were consistent with bulk and x-ray scattering data.
- Anisotropic exchange parameters were determined from intense hexagonal site excitations.
Conclusions:
- The study successfully characterized crystal field excitations in UPd(3).
- The findings validate the use of RPA for describing these excitations in uranium compounds.
- The determined anisotropic exchange parameters provide insights into the magnetic interactions within UPd(3).
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