Soft X-ray Spectroscopic Study of the Ferromagnetic Insulator V0.82Cr0.18O2
The chromium-vanadium oxide system V{sub 1-x}Cr{sub x}O{sub 2} (0.1 < x < 0.2) displays both insulating character in the rutile phase and room-temperature ferromagnetism. A combination of x-ray photoemission spectroscopy, resonant inelastic x-ray scattering, and resonant x-ray emission spectroscopy of the V L{sub 3,2}, O K, and Cr L{sub 3,2} edges was used to study the electronic structure near the Fermi level of V{sub 0.82}Cr{sub 0.12}O{sub 2}. Our results show that the chromium enters as Cr{sup 3+} with the d{sup 3} configuration, resulting in the formation of Cr{sup 3+}-V{sup 5+} ion pairs, in contrast to the simple Cr{sup 4+} substitution expected from the end members VO{sub 2} and CrO{sub 2}. The occupied Cr 3d orbital is located -2 eV below the Fermi level. Comparison with the parent material VO{sub 2} reveals significant changes in the O 2p bandwidth and increased O 2p-V 3d hybridization in V{sub 0.82}Cr{sub 0.12}O{sub 2}, which are attributed to the reduced atomic spacing upon doping. Two energy loss features due to d-d* transitions are observed at 0.95 and 1.75 eV in the V L{sub 3}-edge x-ray scattering spectra and are explained in terms of the splitting of the t{sub 2g}-derived {pi} band.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Sponsoring Organization:
- USDOE SC OFFICE OF SCIENCE (SC)
- DOE Contract Number:
- DE-AC02-98CH10886
- OSTI ID:
- 1042118
- Report Number(s):
- BNL-97796-2012-JA; TRN: US1202744
- Journal Information:
- Physical Review. B, Condensed Matter and Materials Physics, Vol. 82, Issue 23
- Country of Publication:
- United States
- Language:
- English
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