%0 Journal Article
%K Transmission electron microscopy
%K Room temperature
%K Phase transitions
%K Ferroelectric materials
%K Nanocrystals
%K Ferroelectricity
%K Nanoscale
%K Ferroelectric
%K Atomic scale
%K Colloidal
%K Colloidal nanocrystals
%K Germanium telluride
%K GeTe
%K Linear components
%K Polar
%K Polar ordering
%K Germanium
%A M.J Polking
%A J.J Urban
%A D.J Milliron
%A H Zheng
%A E Chan
%A M.A Caldwell
%A S Raoux
%A C.F Kisielowski
%A Joel W Ager
%A Ramamoorthy Ramesh
%A A.P Alivisatos
%B Nano Letters
%D 2011
%G eng
%P 1147-1152
%R 10.1021/nl104075v
%T Size-dependent polar ordering in colloidal GeTe nanocrystals
%V 11
%X The question of the nature and stability of polar ordering in nanoscale ferroelectrics is examined with colloidal nanocrystals of germanium telluride (GeTe). We provide atomic-scale evidence for room-temperature polar ordering in individual nanocrystals using aberration-corrected transmission electron microscopy and demonstrate a reversible, size-dependent polar-nonpolar phase transition of displacive character in nanocrystal ensembles. A substantial linear component of the distortion is observed, which is in contrast with theoretical reports predicting a toroidal state. © 2011 American Chemical Society.