title: Electronic properties of electrical vortices in ferroelectric nanocomposites from large-scale ab initio computations.
abstract: An original ab initio procedure is developed and applied to a ferroelectric nanocomposite, in order to reveal the effect of electrical vortices on electronic properties. Such procedure involves the combination of two large-scale numerical schemes, namely, the effective Hamiltonian (to incorporate ionic degrees of freedom) and the linear-scaling three-dimensional fragment method (to treat electronic degrees of freedom). The use of such procedure sheds some light into the origin of the recently observed current that is activated at rather low voltages in systems possessing electrical vortices. It also reveals a novel electronic phenomena that is a systematic control of the type of the band-alignment (i.e., type I versus type II) within the same material via the temperature-driven annihilation/formation of electrical topological defects.
authors.affiliation: †Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, Arkansas 72701, United States.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Gui
authors.affiliation: ‡Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
authors.forename: Lin-Wang
authors.initials: LW
authors.lastname: Wang
authors.affiliation: †Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, Arkansas 72701, United States.
authors.forename: L
authors.initials: L
authors.lastname: Bellaiche
keywords: Topological defect; band alignment; conductivity; electrical vortex; linear scaling method; nanocomposite