Electronic structure of the ferroelectric layered perovskite SrBi{sub 2}Ta{sub 2}O{sub 9}
- Engineering Department, Cambridge University, Cambridge CB21PZ (United Kingdom)
- Sandia National Laboratories, Albuquerque, New Mexico 87185-1349 (United States)
- Sony Corporation Research Center, Hodogaya-ku, Yokohama-shi 240 (Japan)
The band structure of the layered perovskite SrBi{sub 2}Ta{sub 2}O{sub 9} (SBT) was calculated by tight binding and the valence band density of states was measured by x-ray photoemission spectroscopy. We find both the valence and conduction band edges to consist of states primarily derived from the Bi{endash}O layer rather than the perovskite Sr{endash}Ta{endash}O blocks. The valence band maximum arises from O {ital p} and some Bi {ital s} states, while the conduction band minimum consists of Bi {ital p} states, with a wide band gap of 5.1 eV. It is argued that the Bi{endash}O layers largely control the electronic response whereas the ferroelectric response originates mainly from the perovskite Sr{endash}Ta{endash}O block. Bi and Ta centered traps are calculated to be shallow, which may account in part for its excellent fatigue properties. {copyright} {ital 1996 American Institute of Physics.}
- Research Organization:
- Sandia National Laboratories (SNL), Albuquerque, NM, and Livermore, CA (United States)
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 383719
- Journal Information:
- Applied Physics Letters, Vol. 69, Issue 12; Other Information: PBD: Sep 1996
- Country of Publication:
- United States
- Language:
- English
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