Size-dependent polar ordering in colloidal GeTe nanocrystals

Journal Article

Polking, M.J, J.J Urban, D.J Milliron, H Zheng, E Chan, M.A Caldwell, S Raoux, C.F Kisielowski, Joel W Ager, Ramamoorthy Ramesh, A.P Alivisatos

10.1021/nl104075v

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.

Nano Letters

11

2011

15306984

cited By 65

Ramesh Lab