Coherent ferroelectric switching by atomic force microscopy

A classical energy approach is applied to study polarization reversal induced by voltage-modulated atomic force microscopy in ferroelectric single crystals and thin films. Formations of a reversed domain nucleus, its forward growth in a bulk, and sidewise expansions in a film are described by analyzing the domain energetics under an increasing external bias. It is shown that (i) the nucleation is possible even at low driving voltages, (ii) contact instability is typical for a domain in approaching an electrode, and (iii) different stages of the switching process are delimited on the voltage scale.