[Zurück]

G. Lantz, M. Hajlaoui, E. Papalazarou, V. l Jacques, A. Mazzotti, M. Marsi, S. Lupi, M. Amati, L. Gregoratti, L. Si, Z. Zhong, K. Held:
"Surface Effects on the Mott-Hubbard Transition in Archetypal V2O3";
Physical Review Letters, 115 (2015), S. 236802-1 - 236802-6.

We present an experimental and theoretical study exploring surface effects on the evolution of the metal-insulator transition in the model Mott-Hubbard compound Cr-doped V2O3. We find a microscopic domain formation that is clearly affected by the surface crystallographic orientation. Using scanning photoelectron microscopy and x-ray diffraction, we find that surface defects act as nucleation centers for the formation of domains at the temperature-induced isostructural transition and favor the formation of microscopic metallic regions. A density-functional theory plus dynamical mean-field theory study of different surface terminations shows that the surface reconstruction with excess vanadyl cations leads to doped, and hence more metallic, surface states, which explains our experimental observations.

http://dx.doi.org/10.1103/PhysRevLett.115.236802