Minority-spin t2g states and the degree of spin polarization in ferromagnetic metallic La2-2xSr1+2xMn2O7 (x =0.38)
Abstract
Using angle-resolved photoemission spectroscopy (ARPES), we investigate the electronic band structure and Fermi surface of ferromagnetic La2-2xSr1+2xMn2O7 (x =0.38). Besides the expected two hole pockets and one electron pocket of majority-spin eg electrons, we show an extra electron pocket around the Γ point. A comparison with first-principles spin-polarized band-structure calculations shows that the extra electron pocket arises from t2g electrons of minority-spin character, indicating this compound is not a complete half-metallic ferromagnet, with similar expectations for lightly-doped cubic manganites. However, our data suggest that a complete half-metallic state is likely to be reached as long as the bandwidth is mildly reduced. Moreover, the band-resolved capability of ARPES enables us to investigate the band structure effects on spin polarization for different experimental conditions.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2013
- Bibcode:
- 2013APS..MARA17009S