High pressure studies on the switching mechanism of the ground state in uranium 5f system

2015 Fiscal Year Final Research Report

• Project/Area Number: 25400386
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Condensed matter physics II
• Research Institution: Japan Atomic Energy Agency
• Principal Investigator: Tateiwa Naoyuki 国立研究開発法人日本原子力研究開発機構, 原子力科学研究部門 先端基礎研究センター, 研究主幹 (50346821)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: ウラン化合物 / 高圧実験 / 強磁性超伝導

Outline of Final Research Achievements

The purpose of the present project is to study the change of the electric state associated with pressure-induced phase transition in uranium compounds. We also study the physical property of the 5f electron system around magnetic to non-magnetic phase boundary. In addition, the development of high-pressure cell is planed. We find new critical scaling law of magnetization around the ferromagnetic transition temperature in UGe2 and URhGe. We improve the performance of miniature ceramic anvil cell mCAC for magnetic measurements under high pressure. We reduce background magnetization in mCAC by changing cell design. With this improvement, we have studied pressure-induced ferromagnetic in b-US2 and YbCu2Si2. In b-US2, the insulator-metal transition occurs around 4 GPa. We have found the strong ferromagnetic phase is induced in the metallic phase. The ferromagnetic properties in the pressure-induced phase are determined in YbCu2Si2.

Free Research Field

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