title: Tunable metallic conductance in ferroelectric nanodomains.
abstract: Metallic conductance in charged ferroelectric domain walls was predicted more than 40 years ago as the first example of an electronically active homointerface in a nonconductive material. Despite decades of research on oxide interfaces and ferroic systems, the metal-insulator transition induced solely by polarization charges without any additional chemical modification has consistently eluded the experimental realm. Here we show that a localized insulator-metal transition can be repeatedly induced within an insulating ferroelectric lead-zirconate titanate, merely by switching its polarization at the nanoscale. This surprising effect is traced to tilted boundaries of ferroelectric nanodomains, that act as localized homointerfaces within the perovskite lattice, with inherently tunable carrier density. Metallic conductance is unique to nanodomains, while the conductivity of extended domain walls and domain surfaces is thermally activated. Foreseeing future applications, we demonstrate that a continuum of nonvolatile metallic states across decades of conductance can be encoded in the size of ferroelectric nanodomains using electric field.
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. maksymovychp@ornl.gov
authors.forename: Peter
authors.initials: P
authors.lastname: Maksymovych
authors.forename: Anna N
authors.initials: AN
authors.lastname: Morozovska
authors.forename: Pu
authors.initials: P
authors.lastname: Yu
authors.forename: Eugene A
authors.initials: EA
authors.lastname: Eliseev
authors.forename: Ying-Hao
authors.initials: YH
authors.lastname: Chu
authors.forename: Ramamoorthy
authors.initials: R
authors.lastname: Ramesh
authors.forename: Arthur P
authors.initials: AP
authors.lastname: Baddorf
authors.forename: Sergei V
authors.initials: SV
authors.lastname: Kalinin
mesh_terms: D004553:Electric Conductivity; D004574:Electromagnetic Fields; D046911:Macromolecular Substances / Q000737:chemistry / Q000528:radiation effects; D008422:Materials Testing; D008670:Metals / Q000737:chemistry* / Q000528:radiation effects*; D008968:Molecular Conformation / Q000528:radiation effects; D049329:Nanostructures / Q000737:chemistry* / Q000528:radiation effects* / Q000648:ultrastructure; D013499:Surface Properties / Q000528:radiation effects
chemical_list: D046911:Macromolecular Substances; D008670:Metals