Extended Data Fig. 1: Growth and transfer of freestanding PTO/STO bilayers.
From: High-density switchable skyrmion-like polar nanodomains integrated on silicon
a, Schematic illustration of the process of heterostructure growth and membrane lift-off. The PTO/STO heterostructure is first grown on TiO2-terminated (001) STO substrates with a SAO water-soluble sacrificial layer (left) and then the bilayer is attached to a supporting polymer and released from the substrate by dissolving away the SAO layer by water (middle). Finally, the bilayer is transferred onto the desired substrate (right). b, The Reflection High Energy Electron Diffraction (RHEED) patterns for as-grown PTO(16 u.c.)/STO(10 u.c.)/SAO(6 u.c.) film on (001) STO substrate. c, Atomic force microscopy characterization of (001) STO substrate (left) and as-grown films (right) showing an atomically smooth surface with unit cell step terraces. Scale bar, 1 µm. d, Low-magnification planar-view HADDF image of the freestanding (PbTiO3)20/(SrTiO3)10 bilayer transferred to a holey carbon TEM grid and selected area electron diffraction (SAED) taken along [001] zone axis (inset), showing the single-crystal structure of the bilayer. Scale bar, 1 µm.
