Metal-Insulator Transitions in Ti_4O_7 : Pressure-Induced Melting of the Electron Pairs
We discovered a pressure-induced metal-insulator transition in Ti<SUB>4</SUB>O<SUB>7</SUB> which is a bipolaronic insulator at ambient pressure. In the pressure-induced metallic phase, the resistivity shows T<SUP>2</SUP>-behavior att low temperatures. From the remarkably large magnitude of T<SUP>2</SUP>-resistivity and its pressure dependence, we suggest that electron correlations are very likely the primal origin of the bipolaronic insulator phase of Ti<SUB>4</SUB>O<SUB>7</SUB>. In spite of early expectations, superconductivity was not observed down to 3 K.
- 高圧力の科学と技術 = The Review of high pressure science and technology
高圧力の科学と技術 = The Review of high pressure science and technology 7, 453-455, 1998
The Japan Society of High Pressure Science and Technology