1 research outputs found
Large Scale Two-Dimensional Flux-Closure Domain Arrays in Oxide Multilayers and Their Controlled Growth
Ferroelectric
flux-closures are very promising in high-density
storage and other nanoscale electronic devices. To make the data bits
addressable, the nanoscale flux-closures are required to be periodic
via a controlled growth. Although flux-closure quadrant arrays with
180° domain walls perpendicular to the interfaces (V-closure)
have been observed in strained ferroelectric PbTiO<sub>3</sub> films,
the flux-closure quadrants therein are rather asymmetric. In this
work, we report not only a periodic array of the symmetric flux-closure
quadrants with 180° domain walls parallel to the interfaces (H-closure)
but also a large scale alternative stacking of the V- and H-closure
arrays in PbTiO<sub>3</sub>/SrTiO<sub>3</sub> multilayers. On the
basis of a combination of aberration-corrected scanning transmission
electron microscopic imaging and phase field modeling, we establish
the phase diagram in the layer-by-layer two-dimensional arrays versus
the thickness ratio of adjacent PbTiO<sub>3</sub> films, in which
energy competitions play dominant roles. The manipulation of these
flux-closures may stimulate the design and development of novel nanoscale
ferroelectric devices with exotic properties