| AVS 54th International Symposium | |
| Electronic Materials and Processing | Wednesday Sessions |
| Session EM-WeA |
| Session: | Growth and Characterization of Complex Oxides |
| Presenter: | S.V. Kalinin, Oak Ridge National Laboratory |
| Authors: | S.V. Kalinin, Oak Ridge National Laboratory S. Jesse, Oak Ridge National Laboratory B.J. Rodriguez, Oak Ridge National Laboratory I. Vrejoiu, Max Planck Institute of Microstructure Physics, Germany D. Hesse, Max Planck Institute of Microstructure Physics, Germany M. Alexe, Max Planck Institute of Microstructure Physics, Germany Y.H. Chu, University of California, Berkeley R. Ramesh, University of California, Berkeley S. Choudhury, Pennsylvania State University L.Q. Chen, Pennsylvania State University E.A. Eliseev, National Academy of Science of Ukraine A.N. Morozovska, National Academy of Science of Ukraine |
| Correspondent: | Click to Email |
Ferroelectric polarization switching in non-volatile memory and high density data storage devices is governed by a number of nucleation centers that account for the experimentally observed low values of coercive fields. Despite 50 years of research, the microstructural origins of the Landauer paradox (switching fields corresponding to implausibly large nucleation activation energies) are still a mystery. Here, Switching Spectroscopy Piezoresponse Force Microscopy (SS-PFM) is developed as a quantitative tool for real-space mapping of polarization dynamics in ferroelectrics. SS-PFM is an extension of PFM spectroscopy that involves the acquisition and analysis of multiple hysteresis curves at every point in an image to extract maps of parameters describing the local switching properties. In nanodots, the non-uniform work of switching was imaged with ~10 nm resolution within 50 nm ferroelectric nanoparticles. In epitaxial lead zirconate-titanate thin film, the spatial distribution of the switching centers is obtained and the components of thermal (variation in depolarization energy of domain wall energy) and field (built-in polarization) disorder are extracted independently. Phase-field modeling of PFM switching yields nearly quantitative agreement between experimentally measured and calculated nucleation biases on the free surfaces and in the vicinity of the in-plane domains. This indicates that switching in PFM is close to the intrinsic thermodynamic limit. Further prospects of SS-PFM studies of ferroelectric devices and nanostructures for information technology are discussed. Research supported by the Division of Materials Science and Engineering, Basic Energy Sciences, U.S. Department of Energy at Oak Ridge National Laboratory, which is managed by UT-Battelle, LLC.