title: Domain-wall conduction in ferroelectric BiFeO3controlled by accumulation of charged defects.
abstract: Mobile charged defects, accumulated in the domain-wall region to screen polarization charges, have been proposed as the origin of the electrical conductivity at domain walls in ferroelectric materials. Despite theoretical and experimental efforts, this scenario has not been directly confirmed, leaving a gap in the understanding of the intriguing electrical properties of domain walls. Here, we provide atomic-scale chemical and structural analyses showing the accumulation of charged defects at domain walls in BiFeO3. The defects were identified as Fe4+cations and bismuth vacancies, revealing p-type hopping conduction at domain walls caused by the presence of electron holes associated with Fe4+. In agreement with the p-type behaviour, we further show that the local domain-wall conductivity can be tailored by controlling the atmosphere during high-temperature annealing. This work has possible implications for engineering local conductivity in ferroelectrics and for devices based on domain walls.
authors.affiliation: Electronic Ceramics Department, Jozef Stefan Institute, 1000 Ljubljana, Slovenia.
authors.forename: Tadej
authors.initials: T
authors.lastname: Rojac
authors.affiliation: Electronic Ceramics Department, Jozef Stefan Institute, 1000 Ljubljana, Slovenia.
authors.forename: Andreja
authors.initials: A
authors.lastname: Bencan
authors.affiliation: Department of Materials Chemistry, National Institute of Chemistry, 1000 Ljubljana, Slovenia.
authors.forename: Goran
authors.initials: G
authors.lastname: Drazic
authors.affiliation: Research Institute of Electronics, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu-shi, 432-8561, Japan.
authors.forename: Naonori
authors.initials: N
authors.lastname: Sakamoto
authors.affiliation: Electronic Ceramics Department, Jozef Stefan Institute, 1000 Ljubljana, Slovenia.
authors.forename: Hana
authors.initials: H
authors.lastname: Ursic
authors.affiliation: Advanced Materials Department, Jozef Stefan Institute, 1000 Ljubljana, Slovenia.
authors.forename: Bostjan
authors.initials: B
authors.lastname: Jancar
authors.affiliation: Department of Inorganic Chemistry and Technology, Jozef Stefan Institute, 1000 Ljubljana, Slovenia.
authors.forename: Gasper
authors.initials: G
authors.lastname: Tavcar
authors.affiliation: Electronic Ceramics Department, Jozef Stefan Institute, 1000 Ljubljana, Slovenia.|Jozef Stefan International Postgraduate School, 1000 Ljubljana, Slovenia.
authors.forename: Maja
authors.initials: M
authors.lastname: Makarovic
authors.affiliation: Electronic Ceramics Department, Jozef Stefan Institute, 1000 Ljubljana, Slovenia.
authors.forename: Julian
authors.initials: J
authors.lastname: Walker
authors.affiliation: Electronic Ceramics Department, Jozef Stefan Institute, 1000 Ljubljana, Slovenia.
authors.forename: Barbara
authors.initials: B
authors.lastname: Malic
authors.affiliation: Laboratory for Ferroelectrics and Functional Oxides, Swiss Federal Institute of Technology-EPFL, 1015 Lausanne, Switzerland.
authors.forename: Dragan
authors.identifier: 0000-0002-9596-7438
authors.initials: D
authors.lastname: Damjanovic