Theoretical phase diagram of ultrathin films of incipient ferroelectrics
arXiv:cond-mat/0702285 · doi:10.1063/1.2748844
Abstract
We have used a first-principles-based scheme to compute the temperature-versus-misfit strain ``Pertsev'' phase diagram of ultrathin films of {\sl incipient} ferroelectric KTaO. Our results suggest that, at variance with the bulk material, KTaO ultrathin films cannot be described as quantum paraelectrics. Rather, the behavior of the films is largely determined by surface/interface effects that favor ferroelectricity and the imperfect screening of the depolarizing fields. This leads to Pertsev phase diagrams that are qualitatively similar to those of {\sl normal} ferroelectrics such as BaTiO.
4 pages, 2 figures