Extended Data Fig. 8: STM and AFM images of other types of domain walls.
From: Two-dimensional ferroelectricity in a single-element bismuth monolayer
a–c, STM images (left panel), AFM images (middle panel) and corresponding atomic models (right panel) of the 54° inclined 180° head-to-head domain wall (a), 90° head-to-tail domain wall (b) and 90° head-to-head domain wall (c). Orange arrows denote the directions of polarization. Setpoints of the STM images in (a–c) are V = 100 mV, I = 10 pA (a), V = 100 mV, I = 30 pA (b), V = 100 mV, I = 50 pA (c). Tip heights to measure the AFM images in (a–c) are z = −250 pm (a), −250 pm (b), −200 pm (c), relative to the height determined by the setpoint V = 100 mV, I = 10 pA above normal Bi surface.
