Low-temperature specific heat study of SrCu2(BO3)2 with an exactly solvable ground state

被引:24
作者
Kageyama, H [1 ]
Onizuka, K [1 ]
Ueda, Y [1 ]
Nohara, M [1 ]
Suzuki, H [1 ]
Takagi, H [1 ]
机构
[1] Univ Tokyo, Grad Sch Frontier Sci, Tokyo 1138656, Japan
关键词
Magnetic Field; Elementary Particle; Quantum Field Theory; Dime Model; Zeeman Splitting;
D O I
10.1134/1.559083
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
The specific heat of a two-dimensional spin gap system SrCu2(BO3)(2) realizing the Shastry-Sutherland model was measured between 1.3 and 25 K under various magnetic fields up to 12 T. The analysis based on an isolated dimer model in a low temperature region revealed that the value of the spin gap at zero field is Delta = 34.4 K. It turned out that Delta decreases in proportion to H due to the Zeeman splitting of the excited triplet levels. This simplest model, however, fails to reproduce the result in a high-temperature region, suggesting rather strong spin-spin correlation of the system. (C) 2000 MAIK "Nauka/Interperiodica".
引用
收藏
页码:129 / 132
页数:4
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