In:
physica status solidi (b), Wiley, Vol. 249, No. 8 ( 2012-08), p. 1559-1565
Abstract:
Single crystals of the p‐type semiconductor CuAlO 2 , synthesized from the CuO flux method, have been investigated by electron paramagnetic resonance (EPR) spectroscopy at temperatures from 3.5 to 294 K. EPR spectra reveal an axial Cr 3+ center and an axial Fe 3+ center, presumably arising from impurities in the starting materials. The Cr 3+ center at 294 K is characterized by g = 1.979(1) and D = − 7803(3) × 10 −4 cm −1 . The Fe 3+ center at 294 K has g // = 1.9942(1), g ⟂ = 1.9964(1), D = 261.9(3) × 10 −4 cm −1 , $B_{4}^{0} = 4.533(3) \times 10^{- 4} \,{\rm cm}^{- 1} $ , and $B_{4}^{3} = 104.23(3) \times 10^{- 4} \,{\rm cm}^{- 1} $ . These spin‐Hamiltonian parameters, evaluated by superposition model analyses and periodic density functional theory (DFT) calculations, suggest that both Cr 3+ and Fe 3+ occupy the Al 3+ site but the latter involves distortion related to perturbation from a substitutional Cu + ion at the nearest Al site. This difference in the local structure between Fe 3+ and Cr 3+ explains their contrasting effects on the p‐type conductivity in CuAlO 2 .
Type of Medium:
Online Resource
ISSN:
0370-1972
,
1521-3951
DOI:
10.1002/pssb.201147466
Language:
English
Publisher:
Wiley
Publication Date:
2012
detail.hit.zdb_id:
208851-4
detail.hit.zdb_id:
1481096-7
