Figure 1: Shapes of the domains formed after switching by sequence of bipolar triangular pulses.
From: Ionic field effect and memristive phenomena in single-point ferroelectric domain switching

(a) 1, (b) 2, (c) 3 and (d) 5 complete cycles. (e) Domain shape evolution at different stages of the switching pulse. Relative humidity H=75% and pulse amplitude Usw=80 V. Scale bar, 100 nm.