Proton Spin-Lattice Relaxation in the Quasi-One-Dimensional S=1 Heisenberg Antiferromagnet Ni(C2H8N2)2NO2(ClO4)
Proton Spin-Lattice Relaxation in the Quasi-One-Dimensional S=1 Heisenberg Antiferromagnet Ni(C2H8N2)2NO2(ClO4)
复制标题
准一维 S=1 海森堡反铁磁体 Ni(C2H8N2)2NO2(ClO4) 中的质子自旋晶格弛豫
DOI：
10.1143/jpsj.59.1135
复制
发表时间：
1990
影响因子：
1.7
通讯作者：
S. Maegawa
中科院分区：
文献类型：
--
作者：
T. Goto;N. Fujiwara;T. Kohmoto;S. Maegawa
在1.4 ~ 77 K温度范围内测量了S =1的Haldane带隙体系Ni（C2 H8 N2）2NO 2（ClO 4）的质子自旋晶格弛豫时间T1。弛豫速率T1 - 1随温度的降低而降低超过三个数量级，从而表明反铁磁短程有序的发展不足。根据绝缘顺磁体理论，利用静态磁化率数据分析了6 K以上T_（1 - 1）的单调下降。为了解释T1 - 1在6 K以下的行为，它伴随着一个圆形的峰值，我们考虑了核拉莫尔周期的量级的局部场涨落的影响，这与来自基态的磁激发有关。
Proton spin-lattice relaxation time T 1 in the Haldane-gap system with S =1, Ni(C 2 H 8 N 2 ) 2 NO 2 (ClO 4 ), was measured at temperatures between 1.4 K and 77 K. The relaxation rate T 1 -1 decreased over more than three orders of magnitude with decreasing temperature, thus suggesting scarce development of the antiferromagnetic short-range order. Monotonous decrease of T 1 -1 above 6 K was analyzed on the basis of the theory for insulating paramagnets using static susceptibility data. To explain the behavior of T 1 -1 below 6 K, which accompanies a rounded peak, we consider the effect of local-field fluctuation of the order of the nuclear Larmor period, which is associated with magnetic excitation from the nonmagnetic ground state.