title: Polarization control at spin-driven ferroelectric domain walls.
abstract: Unusual electronic states arise at ferroelectric domain walls due to the local symmetry reduction, strain gradients and electrostatics. This particularly applies to improper ferroelectrics, where the polarization is induced by a structural or magnetic order parameter. Because of the subordinate nature of the polarization, the rigid mechanical and electrostatic boundary conditions that constrain domain walls in proper ferroics are lifted. Here we show that spin-driven ferroelectricity promotes the emergence of charged domain walls. This provides new degrees of flexibility for controlling domain-wall charges in a deterministic and reversible process. We create and position a domain wall by an electric field in Mn0.95Co0.05WO4. With a magnetic field we then rotate the polarization and convert neutral into charged domain walls, while its magnetic properties peg the wall to its location. Using atomistic Landau-Lifshitz-Gilbert simulations we quantify the polarization changes across the two wall types and highlight their general occurrence.
authors: Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 4, CH-8093 Zurich, Switzerland.
authors: Naëmi
authors: N
authors: Leo
authors: Department of Physics and Astronomy, Uppsala University, PO Box 516, 751 20 Uppsala, Sweden.
authors: Anders
authors: A
authors: Bergman
authors: CNRS, University of Bordeaux, ICMCB, UPR 9048, F-33600 Pessac, France.
authors: Andres
authors: A
authors: Cano
authors: Department of Physics and Texas Center for Superconductivity, University of Houston, 3201 Cullen Boulevard, Houston, Texas 77204, USA.
authors: Narayan
authors: N
authors: Poudel
authors: Department of Physics and Texas Center for Superconductivity, University of Houston, 3201 Cullen Boulevard, Houston, Texas 77204, USA.
authors: Bernd
authors: B
authors: Lorenz
authors: Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 4, CH-8093 Zurich, Switzerland.
authors: Manfred
authors: M
authors: Fiebig
authors: Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 4, CH-8093 Zurich, Switzerland.
authors: Dennis
authors: D
authors: Meier