Mesoscale flux-closure domain formation in single-crystal BaTiO3

Abstract

Over 60 years ago, Charles Kittel predicted that quadrant domains should spontaneously form in small ferromagnetic platelets. He expected that the direction of magnetization within each quadrant should lie parallel to the platelet surface, minimizing demagnetizing fields,and that magnetic moments should be configured into an overall closed loop, or flux-closure arrangement. Although now a ubiquitous observation in ferromagnets, obvious flux-closure patterns have been somewhat elusive in ferroelectric materials. This is despite the analogous behaviour between these two ferroic subgroups and the recent prediction of dipole closure states by atomistic simulations research. Here we show Piezoresponse Force Microscopy images of mesoscopic dipole closure patterns in free-standing, single-crystal lamellae of BaTiO3. Formation of these patterns is a dynamical process resulting from system relaxation after the BaTiO3 has been poled with a uniform electric field. The flux-closure states are composed of shape conserving 90° stripe domains which minimize disclination stresses.

Ferroelectric or non-ferroelectric: Why so many materials exhibit “ferroelectricity” on the nanoscale

“…More complex phenomena are possible for multidomain materials and domain textures; however, these main features are still present. 310,[315][316][317][318][319][320] The (fundamental) detection mechanism for these systems is the converse piezoelectric effect. Here, the strain (and hence surface displacement) is U = QP 2 , where Q is electrostrictive coefficient and P is polarization.…”

Novel high-temperature ferroelectric domain morphology in PbTiO3 ultrathin films

“…A rich variety of new closure domain morphologies, such as Landau-Lifshitz stripe domains [11,12], vortex and triclinic domains [13], have been predicted in PbTiO 3 , and BaTiO 3 thin films under open-circuit boundary conditions using density functional theory, effective Hamiltonian and interatomic potential models [14,15]. Tantalising experimental evidence for these closure domains in platlets and dots of BaTiO 3 has been presented in the form of 90 • stripe superdomains bifurcated by 180 • domain walls [16][17][18] and recent direct observation of vortices in PbTiO 3 /SrTiO 3 superlattices [19].…”

Self-Similar Nested Flux Closure Structures in a Tetragonal Ferroelectric

“…Of course, depolarizing fields are likely to be present at the edges of the PZN-12PT lamellae, and these should drive flux closure in some form. However, previous work on BaTiO 3 [19] and Pb(Zr,Ti)O 3 [17], has already established that the effects of depolarizing fields can be successfully accommodated by flux closure at a single length scale (mesoscale). Additional internal depolarizing fields caused within a mesoscale flux closure object should not be present.…”