"CONDUCTIVITY IS SKIN DEEP
Ferroelectric materials can create an electric field the way iron
magnets create a magnetic field. And because they're so easily
miniaturized, ferroelectrics are being used to permanently store
data in a new generation of so-called smart cards, used for
financial transactions in some countries. But condensed matter
physicists still don't fully understand how these promising
materials work. When an isolated ferroelectric crystal becomes
polarized (the electric field equivalent of "magnetized"), some
decades-old theories predict that its surface should conduct
electricity, even though the crystal itself is an insulator
(nonconducting). Now a Japanese team reports in the 8 January PRL
that they have finally verified this surprising prediction. But not
all experts are convinced.
(Y. Watanabe, M. Okano, and A. Masuda, Phys. Rev. Lett. 86, 332.
COMPLETE Focus story at http://focus.aps.org/v7/st1.html
Link to the paper: http://publish.aps.org/abstract/PRL/v86/p332/)"