Coupling between electrical and mechanical phenomena is ubiquitous in nature and underpins the functionality of materials and systems as diversified as ferroelectrics and multiferroics, electroactive molecules, and biological systems. In ferroelectrics, electromechanical behavior is directly linked to polarization order parameter and hence can be used to study complex phenomena including polarization reversal, domain wall pinning, multiferroic interaction, and electron-lattice coupling. The very basis of functionalities of biological systems is electromechanics - from nerve-controlled muscle contraction on macroscale to cardiac activity and hearing on micro scale and to energy storage in mitochondria, voltage-controlled ion channels and electromotor proteins on nanoscale. More broadly, electromechanical coupling is a key component of virtually all electrochemical transformations, and is a nearly universal part of energy conversion and transport processes. It forms a basis for many device applications, and is directly relevant to virtually all existing and emerging aspects of materials science and nanobiotechnology.

 

    The ubiquity and importance of electromechanics is belied by the lack of systematic interdisciplinary studies, due to, until recently, the dearth of corresponding nanoscale probing tools and the difficulty in quantitatively determining the relatively small electromechanical coupling coefficients. The development of piezoresponse force microscopy (PFM) and piezoelectric nanoindentation technique in the last decade has led to rapid advances in the investigation of electromechanics with unprecedented resolution. In ferroelectric materials, PFM has enabled imaging static and dynamic domain characteristics at the nanometer level, providing direct experimental observations on switching and fatigue, domain-defect interactions, and nucleation mechanisms. The last several years have also witnessed a number of spectacular advances in PFM imaging and characterization of III-V nitrides, the discovery of biological ferroelectricity, and expanding PFM capabilities to liquid and vacuum environments, as well as electrochemical systems in the form of electrochemical strain microscopy (ESM)

 

    This workshop aims to provide in-depth description and recent advances in PFM and nanoscale electromechanics. It will introduce basic principles of PFM operation, relevant instrumental aspects, and image interpretation. The theory of cantilever dynamics, PFM contact mechanics, resolution theory, and their implications for qualitative and quantitative data interpretation will be presented. The recent technical advances, including vector PFM, high-frequency PFM, band-excitation, switching spectroscopy PFM, and imaging and polarization switching in liquids and vacuum, will also be illustrated. For ferroelectric and multiferroic materials, applications of PFM for domain imaging, nucleation center mapping, and probing polarization dynamics in thin films and capacitor structures will be presented. Electromechanical probing of biological materials, soft-condensed matters, and electrochemical systems beyond classical ferroelectric applications will also be discussed in detail. Finally, participants will gain hand-on experience in PFM using various commercial systems during Lab Demos , and are welcome to bring their own samples for testing.

 

    The three-day workshop consists of Tutorial Lectures by PFM pioneers, Topical Lectures by leading scientists in the field, Industrial Lectures from leading PFM manufacturers, and Poster Sessions for attendees to discuss their own work. It also includes extensive Lab Demos for participants to gain hand-on experience in PFM on various commercial systems, for which the attendees can bring their own samples for testing and examinations.

    We look forward to seeing in Nanjing next you. You can also contact us at xiaomeil@nju.edu.cn (Xiaomei Lu) and jjli@uw.edu (Jiangyu Li).