Spin Liquid Studies by Pressure Control of Spin-Liquid-Insulating Phase

2015 Fiscal Year Final Research Report

• Project/Area Number: 25400384
• 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: National Institute for Materials Science
• Principal Investigator: UJI Shinya 国立研究開発法人物質・材料研究機構, 機能性材料研究拠点, 副拠点長 (80344430)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: スピン液体 / 磁気トルク / 磁化率 / 三角格子 / 有機磁性体

Outline of Final Research Achievements

In order to investigate unique spin states in triangular lattices with spin S=1/2, we have measured magnetic properties in a wide temperaure and magnetic field region for k-type magnetic organic conductors. We measured the magnetic properties for k-(BDH-TTP)2FeX4 (X = Br, Cl) and developed an analysis technique of the magnetic torque data. We also performed SQUID and torque measurements for k-H-3(Cat-EDT-TTF)2 in detail and clarified the spin-liquid ground state, showing a constant magnetic susceptibility at low temperatures down to 50mK. We observed that the susceptibility shows divengence behavior at low temperature magnetic fields for k-(BEDT-TTF)2Cu2(CN)3, which can be ascribed to quantum critical behavior. This salt is found to show metallic conductivity at 0.5 GPa, but we cound not see quantum oscillations at low temperatures and high magnetic fields.

Free Research Field

低温強磁場物理