Abstract
We have performed high-resolution ultraviolet photoemission spectroscopy on a weak itinerant ferromagnet ZrZn2 (ferromagnetic transition temperature TCurie=28 K), whose superconductivity with Tc=0.29 K has been recently reported [Pfleiderer, et al., Nature 412 (2001) 58]. We have successfully determined the density of states (DOS) in the valence-band and near EF region. The mass-enhancement factor estimated from the present experiment is about 5, suggesting a strong coupling of electrons with a spin fluctuation and/or phonons. This implies that heavy quasi-particle bands in the vicinity of EF play an important role for the occurrence of the ferromagnetism and the superconductivity in ZrZn2. Although the band calculation predicts the exchange splitting being 70-90 meV, we have observed negligible change in the photoemission spectrum near EF even across TCurie within our energy resolution (7 meV). This suggests that the actual exchange splitting is much smaller and/or the size of the exchange splitting is significantly different for different bands.
Original language | English |
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Pages (from-to) | 889-891 |
Number of pages | 3 |
Journal | Journal of Electron Spectroscopy and Related Phenomena |
Volume | 144-147 |
DOIs | |
Publication status | Published - 2005 Jun |
Keywords
- Density of states
- Ferromagnetism
- Photoemission
- Superconductor
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Radiation
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics
- Spectroscopy
- Physical and Theoretical Chemistry