Control of the electronic states of Ca2RuO4 by uniaxial pressure

Abstract

We study the uniaxial pressure effect on the Mott insulator Ca 2RuO4. It is known that the crystal structure is a crucial parameter to determine the electronic states in this system. We revealed that a metal-insulator(M-I) transition is induced by the uniaxial pressure along the ab-plane at room temperature and the metallic state is sustained under cooling down to 5 K In contrast, such a transition to a metallic state is not observed by the uniaxial pressure along the c-axis. Our experimental results suggest that the elongation of the RuO6 octahedra along the c-axis can trigger the M-I transition. © Published under licence by IOP Publishing Ltd.