在自旋受挫有机导体κ-(ET)₂Cu₂(CN)₃中从自旋液体到费米液体的莫特转变

Mott transition from a spin liquid to a Fermi liquid in the spin-frustrated organic conductor kappa-(ET)2Cu2(CN)3.

作者信息

Kurosaki Y, Shimizu Y, Miyagawa K, Kanoda K, Saito G

机构信息

Department of Applied Physics, University of Tokyo, Tokyo, 113-8656, Japan.

出版信息

Phys Rev Lett. 2005 Oct 21;95(17):177001. doi: 10.1103/PhysRevLett.95.177001. Epub 2005 Oct 18.

DOI:10.1103/PhysRevLett.95.177001

PMID:16383857

Abstract

The pressure-temperature phase diagram of the organic Mott insulator kappa-(ET)2Cu2(CN)3, a model system of the spin liquid on triangular lattice, has been investigated by 1H NMR and resistivity measurements. The spin-liquid phase is persistent before the Mott transition to the metal or superconducting phase under pressure. At the Mott transition, the spin fluctuations are rapidly suppressed and the Fermi-liquid features are observed in the temperature dependence of the spin-lattice relaxation rate and resistivity. The characteristic curvature of the Mott boundary in the phase diagram highlights a crucial effect of the spin frustration on the Mott transition.

摘要

有机莫特绝缘体κ-(ET)2Cu2(CN)3是三角晶格上自旋液体的一个模型体系，其压力-温度相图已通过1H核磁共振和电阻率测量进行了研究。在压力作用下，自旋液体相在莫特转变为金属相或超导相之前一直存在。在莫特转变时，自旋涨落迅速受到抑制，并且在自旋晶格弛豫率和电阻率的温度依赖性中观察到费米液体特征。相图中莫特边界的特征曲率突出了自旋阻挫对莫特转变的关键影响。