Spin-Orbit and Crystal Field excitations in Cerium compounds probed by Resonant Inelastic X-ray Scattering
Event details
| Date | 05.02.2014 |
| Hour | 16:00 |
| Speaker |
Mauro Fanciulli Candidate for a PhD position |
| Location | |
| Category | Conferences - Seminars |
The 4f electronic structure of Cerium atoms is dominated by Spin-Orbit coupling which produces a split into a 2F5/2 state and a 2F7/2 state, but the interaction with the non-spherical electrostatic field generated by the surrounding charges in an actual compound, called Crystal Field, produces a further splitting of the (2j +1)-fold degeneracy because of a lowering of symmetry.
In order to probe low energy excitations in Cerium we performed X-ray Absorption Spectroscopy (XAS) and Resonant Inelastic X-ray Scattering (RIXS) on Nd1.84Ce0.16CuO4, CeRu2P2 and CeCu2Si2. The valence of Cerium in the three compounds is 3+, 4+ and mixed respectively. The different electronic occupation causes different scattering processes when we perform RIXS.
Spin-Orbit excitations are measured in the Ce3+ samples with an energy of 300 meV, which is comparable to previous ARPES measurements. In addition, hints of Crystal Field excitations are observed around 50 meV for the first time by means of X-rays, qualitatively in agreement with atomic multiplet calculations performed with parameters obtained by Inelastic Neutron Scattering.
Measurements were performed at beamline ID08 of the European Synchrotron Radiation Facility (ESRF), Grenoble.
In order to probe low energy excitations in Cerium we performed X-ray Absorption Spectroscopy (XAS) and Resonant Inelastic X-ray Scattering (RIXS) on Nd1.84Ce0.16CuO4, CeRu2P2 and CeCu2Si2. The valence of Cerium in the three compounds is 3+, 4+ and mixed respectively. The different electronic occupation causes different scattering processes when we perform RIXS.
Spin-Orbit excitations are measured in the Ce3+ samples with an energy of 300 meV, which is comparable to previous ARPES measurements. In addition, hints of Crystal Field excitations are observed around 50 meV for the first time by means of X-rays, qualitatively in agreement with atomic multiplet calculations performed with parameters obtained by Inelastic Neutron Scattering.
Measurements were performed at beamline ID08 of the European Synchrotron Radiation Facility (ESRF), Grenoble.
Practical information
- General public
- Free
Organizer
- Hugo Dil