Imaging and alignment of nanoscale 180° stripe domains in ferroelectric thin films

Abstract

Control and imaging of ferroelectric domains over large areas with nanometer resolution in atomically smooth epitaxial Pb(Zr 0.2 Ti 0.8 )O 3 thin films

Imaging Local Polarization in Ferroelectric Thin Films by Coherent X-Ray Bragg Projection Ptychography

“…Both images, though not of the same area, show similar qualitative stripe domain behavior and morphology. Generally, the stripes display a pronounced tendency to align normal to the substrate surface miscut direction, consistent with previous observations in this thin film system [13]. Though they are predominantly straight and regularly spaced (Λ BP P = 23.5 nm, Λ P F M = 23.0 nm), several domains with varying widths and irregular features are seen in both images, possibly due to the local details of the substrate surface beneath the film.…”

“…The resulting depolarizing field is cancelled on the macroscopic scale by the spontaneous formation of nanoscale 180 • stripe domains with polarization orientation alternating into and out of the film, having predictable sizes and polar properties [2,11,12]. Additionally, PbTiO 3 stripe domain patterns are influenced by the SrTiO 3 substrate surface features such as step edges [13]. The film studied in this work was grown to have a thickness such that the equilibrium stripe domain period (Λ ∼ 19 nm) [12] corresponded roughly to the mean terrace spacing of the miscut SrTiO 3 substrate surface (∼ 22.4 nm).…”

Equilibrium and stability of polarization in ultrathin ferroelectric films with ionic surface compensation

“…• stripe domain formation [1][2][3][4][5][6] in which nanoscale domain structures reduce the depolarizing field even when there is little or no electronic or ionic compensation charge at one or both interfaces. A full treatment of equilibrium stripe domains for the ionic compensation case would be valuable in future work.…”

“…[1][2][3][4][5][6] When electrodes are present, electronic charge at the interfaces can stabilize a monodomain polar state, provided that the effective screening length in the electrodes is sufficiently small compared with the film thickness. [6][7][8][9][10][11][12][13][14] In both cases, the Curie point T C is expected to be increasingly suppressed as film thickness decreases because of the residual depolarizing field energy.…”

Controlled stripes of ultrafine ferroelectric domains

“…For very thin films, the existence of 180°stripe domains was evidenced 10 . They were shown not to be straight but instead to form a meandering pattern 11 . Here we focus on the creation of stripe arrays of ferroelastic, non-180°, ultrafine domains during film growth.…”