  The thermodynamics and kinetics of tip-induced polarization switching in
Piezoresponse Force Microscopy in the presence of surface charge defects is
studied using the combination of analytical and numerical techniques. The
signature of the defects in hysteresis loop fine structure and Switching
Spectroscopy PFM images is identified and compared to experimental
observations. An approach for the deconvolution of PFM spectroscopy
measurements to extract relevant defect parameters is derived. This methodology
is universal and can be extended to switching in other ferroics and in
reversible electrochemical processes, establishing a pathway for the
understanding of the thermodynamics and kinetics of phase transitions at a
single defect level.
