Publication Type
Journal
Journal Name
ACS Nano
Publication Date
Page Numbers
3841 to 3852
Volume
6
Issue
5
Abstract
Local electrochemical phenomena on the surfaces of LaAlO3-SrTiO3 heterostructure are explored using unipolar and bipolar dynamic electrochemical strain microscopy (D-ESM). The D-ESM suggests the presence of at least two distinct electrochemical processes, including fast reversible low-voltage process and slow high-voltage process. The latter process is associated with static surface deformations in the sub-nm regime. These behaviors are compared with Kelvin Probe Force Microscopy hysteresis data. The possible origins of observed phenomena are discussed and these studies suggest that charge-writing behavior in LAO-STO include strong surface/bulk electrochemical component and are more complicated than simple screening by surface adsorbates.
