Gapless Quantum Spin Liquid in an Organic Spin-1/2 Triangular-Lattice κ - H3(Cat-EDT-TTF)2

被引:145
作者
Isono, Takayuki [1 ]
Kamo, Hiromichi [1 ]
Ueda, Akira [1 ]
Takahashi, Kazuyuki [2 ]
Kimata, Motoi [1 ]
Tajima, Hiroyuki [1 ]
Tsuchiya, Satoshi [3 ]
Terashima, Taichi [3 ]
Uji, Shinya [3 ]
Mori, Hatsumi [1 ]
机构
[1] Univ Tokyo, ISSP, Kashiwa, Chiba 2778581, Japan
[2] Kobe Univ, Dept Chem, Kobe, Hyogo 6578501, Japan
[3] Natl Inst Mat Sci, Tsukuba, Ibaraki 3050003, Japan
关键词
ANTIFERROMAGNET; STATE; EXCITATIONS; FRUSTRATION; INSULATOR; TORQUE; SALTS; PHASE; MODEL;
D O I
10.1103/PhysRevLett.112.177201
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
We report the results of SQUID and torque magnetometry of an organic spin-1/2 triangular-lattice kappa - H(3)dCat-EDT-TTF)(2). Despite antiferromagnetic exchange coupling at 80-100 K, we observed no sign of antiferromagnetic order down to 50 mK owing to spin frustration on the triangular lattice. In addition, we found nearly temperature-independent susceptibility below 3 K associated with Pauli paramagnetism. These observations suggest the development of gapless quantum spin liquid as the ground state. On the basis of a comparative discussion, we point out that the gapless quantum spin liquid states in organic systems share a possible mechanism, namely the formation of a band with a Fermi surface possibly attributed to spinons.
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页数:5
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