High-pressure synthesis and metallization of a new type of bandwidth-controlled Mott compounds

A series of bandwidth-controlled (SrCa)CrO3 Mott compounds with perovskite crystal structure were synthesized by using high pressure and high temperature conditions. An insulator-to-metal transition was observed in SrCrO3 at 10 GPa. In situ high-pressure X-ray diffraction shows that the crystal structures of Sr/CaCrO3 remain stable in the same pressure range, but there exists an isostructural phase transition as a result of the change of electronic structure in SrCrO3 at 4 GPa, accompanied by an unusual softening of bulk modulus. In addition, the magnetic and thermal transport properties indicate a strange electronic state, due to the strong correlated electron effects in these materials.