Physics. Driving the electron over the edge

Abstract

At low temperatures, many materials, from organics to oxides, undergo a pressure-driven "Mott transition": A small change in the distance between the atoms causes the electrical resistivity of the system to change by many orders of magnitude, without a change in crystal symmetry. In his Perspective, Kotliar highlights the report by Limelette et al., who have investigated the dependence of the resistivity of a doped vanadium oxide on pressure and temperature around the Mott critical endpoint (where the Mott transition becomes continuous). A purely electronic model accounts for the major features of the experiments, but some more detailed features require the coupling between electrons and the crystal lattice to be taken into account.