Electrical transport properties of fulleride superconductors in the vicinity of Mott transition

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K17690
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics II
• Research Institution: Tohoku University
• Principal Investigator: Heguri Satoshi 東北大学, 原子分子材料科学高等研究機構, 助教 (70611648)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: フラーレン超伝導体 / 超伝導 / 磁性 / モット転移 / 電子相関 / 電気輸送特性 / 極端条件下物性

Outline of Final Research Achievements

Eelectrical transport measurements have been very difficult in C60 superconductors and discussion has been made on a basis of experiments on magnetic probes. Temperature evolution of electrical resistivity of fcc fulleride superconductors RbxCs3-xC60 (0.35<x<3) is shown to be successfully measured under various pressure. Temperature dependence of electrical resistivity ranging from the Mott insulating state to a superconducting state via metallic phase was clearly observed. The profile of Mott insulator to metal boundary as a function of C603- volume was renewed and the different features of between the Jahn-Teller metal and the normal metal is not detected in the electrical transport measurements. In addition, on-site coulomb repulsion energy (U) is commented experimentally. We successfully demonstrated that the electronic states of fcc A3C60 system can be tuned systematically by the volume per C603- using the electrical transport measurements.

Free Research Field

分子性固体