Formation of charged ferroelectric domain walls with controlled periodicity

Abstract

Charged domain walls in proper ferroelectrics were shown recently to possess metallic-like conductivity. Unlike conventional heterointerfaces, these walls can be displaced inside a dielectric by an electric field, which is of interest for future electronic circuitry. In addition, theory predicts that charged domain walls may influence the electromechanical response of ferroelectrics, with strong enhancement upon increased charged domain wall density. The existence of charged domain walls in proper ferroelectrics is disfavoured by their high formation energy and methods of their preparation in predefined patterns are unknown. Here we develop the theoretical background for the formation of charged domain walls in proper ferroelectrics using energy considerations and outline favourable conditions for their engineering. We experimentally demonstrate, in BaTiO3 single crystals the controlled build-up of high density charged domain wall patterns, down to a spacing of 7 μm with a predominant mixed electronic and ionic screening scenario, hinting to a possible exploitation of charged domain walls in agile electronics and sensing devices.

Tunable polarization components and electric field induced crystallization in polyvinylidenefluoride: A piezo polymer

“…The electrostatic force within the PVDF during PFM alter the polymer chain causing monomer to rotate in the direction of electric field thus leading to change in the arrangement of irregular amorphous region and converting them to a crystalline region. Literature has also suggested that in the presence of uniform electric field they observe increase in contrast in presence of dc bias which is similar our results . As Pure PVDF is expected to be semi‐crystalline such a transformation of in‐plane phase contrast in the domains is expected to be associated with an amorphous to crystalline transformation.…”

“…Hence, the electrostatic nature of ferroelectric domain arises due to arrangement of the chain in a particular configuration. There are studies that suggest that charged domain wall exists in ferroelectric ceramic because of head‐to‐head or tail‐to‐tail arrangements of domain . The electrostatic strength of domains could possibly have influence on the adjacent ferroelectric domains in certain region.…”

Low Temperature Ionic Conductivity of an Acceptor‐Doped Perovskite: II. Impedance of Single‐Crystal BaTiO3

“…Generalizations concerning the effect of ferroelectric domains on ionic conduction will be avoided. The authors will admit that domain engineered samples with much finer sized domain configurations could have more considerable effects on the results …”

Magnetization Reversal in Fe/BaTiO3(110) Heterostructured Multiferroics

“…Also, the polarization direction along [001] pc or [00‐1] pc coexists along with those domains. The different possible configuration of these domain states such as head‐head or tail‐tail and head‐tail with 90° and 180° orientations becomes possible in T phase on (110) surface, thereby resulting in magnetically isotropic Fe film (for possible ferroelectric domain configurations, see Supporting Information, Figure S2). The twofold symmetry of the magnetic anisotropy in O and R phases is likely associated with the projection of the polarization orientation onto (110) plane.…”

“…This indicates that the magnetization process is strongly coupled to the ferroelectric domain structures. In the present case, the combination of in‐plane head‐head, tail‐tail and head‐tail domains oriented along [100] pc , [010] pc , and [001] pc with 90° and 180° arrangement makes (110) plane highly complex . When a large E above the E C (±5 kV cm −1 ) is applied, the projections of polarization vectors along either [100] pc or [‐100] pc , [010] pc or [0‐10] pc and [001] pc or [00‐1] pc are fundamentally different for positive and negative applied electric fields.…”