Fig. 1.

Surface depressions developed by radial defects upon heating. a PolScope image of a flat LCE coating at 23 °C which maps the optical retardance and the director orientation. Scale bar, 50 μm. b 3D image of surface topography of LCE coating at 100 °C with developed depressions at radial defects, as observed using DHM. c DHM image of the LCE surface at 100 °C used to extract the surface topography. Scale bar, 100 μm. d Surface profiles along line MM’ in (c) at 23, 60, 100 °C. e Activation force density f map calculated for region outlined by a red box in (a, c)