Nanoscale Disorder in CaCu3Ti4O12: A New Route to Enhanced Dielectric Response
Significant nanoscale disorder of Cu and Ca atomic substitution is observed in CaCu{sub 3}Ti{sub 4}O{sub 12}, based on our integrated study using quantitative electron diffraction and extended x-ray absorption fine structure. Unambiguous identification of this previously omitted disorder is made possible by the unique sensitivity of these probes to valence-electron distribution and short-range order. Furthermore, first-principles-based theoretical analysis indicates that the Ca-site Cu atoms possess partially filled degenerate e{sub g} states, suggesting significant boost of dielectric response from additional low-energy electronic contributions. Our study points to a new route of enhancing dielectric response in transitional metal oxides by exploiting the strong electronic correlation beyond classical static pictures.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States). National Synchrotron Light Source
- Sponsoring Organization:
- Doe - Office Of Science
- DOE Contract Number:
- DE-AC02-98CH10886
- OSTI ID:
- 930544
- Report Number(s):
- BNL-80644-2008-JA; PRLTAO; TRN: US200904%%779
- Journal Information:
- Physical Review Letters, Vol. 99; ISSN 0031-9007
- Country of Publication:
- United States
- Language:
- English
Similar Records
Nanoscale Disorder and Local Electronic Properties of CaCu3Ti4O12: An Integrated Study of Electron, Neutron, and X-ray Diffraction, X-ray Absorption Fine Structure, and First-principles Calculations
Nanoscale Disorder and Local Electronic Properties of CaCu,Ti,012: An Integrated Study of Electron, Neutron and X-ray Diffraction, X-ray Absorption Fine Structure and First Principles Calculations