CNMS User Program Highlight Nanoscale Ferroelectricity in Crystalline γ Glycine

1. CNMS User Program Highlight Nanoscale Ferroelectricity in Crystalline γGlycine Alejandro Heredia,1 Vincent Meunier,2 Igor K. Bdikin,3 José Gracio,3 Nina Balke,4 Stephen Jesse, 4 Alexander Tselev,4 Pratul Agarwal, 4 Bobby G. Sumpter, 4 Sergei V. Kalinin, 4 Andrei L. Kholkin1 1Department of Ceramics and Glass Engineering & CICECO, University of Aveiro, 3810-193 Aveiro, Portugal; 2Physics, Astronomy and Applied Physics Department, Rensselaer Polytechnic Institute, Troy,NY ; 3Nanotechnology Research Div., Centre for Mechanical Technology & Automation, University of Aveiro, 3810-193 Aveiro, Portugal; 4Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN (b) (a) • Achievement • First proof that simplest amino acid, γglycine, is ferroelectric. • Piezoresponse force microscopy (PFM) and molecular simulations are used to show proof and origin of ferroelectricity. • Ferroelectric switching occurs via molecule rotation and crystal formation. • Important for high-density organic memory devices. PFM: (a) PFM image of glycine showing domains. (b) Local piezoelectric hysteresis loops for two different domains. (b) (c) (a) Force-field simulations: (a) Number of switched glycine molecules. (b) Side-view of the glycine crystal after application of fields of 7.38 V/nm and (c) 9.55 V/nm. A. Heredia et al., Nanoscale Ferroelectricity in Crystalline γGlycine, Adv. Func. Mater., doi: 10.1002/adfm.201103011(2012). This research was supported in part at the Center for Nanophase Materials Sciences, which is sponsored at Oak Ridge National Laboratory by the Scientific User Facilities Division, Office of Basic Energy Sciences, U.S. Department of Energy.