Metal-Insulator Transition of BaCo_1-xNi_xS₂ Induced by Pressure and Carrier Number Control

Abstract

In a quasi two dimensional system, BaCoS₂, the Mott metal-insulator transition can be induced not only by the Ni-substitution for Co but also by the external pressure. Various physical properties have been studied systematically around these Mott transitions. Based on the electronic structure deduced here, the differences between the electronic states near these transitions are discussed in relation to the properties of the anomalous metallic phase of high-T_c oxides.