High field 1H-NMR study around a 1/4 plateau of quantum spin dimer system NH4CuCl3
High field 1H-NMR study around a 1/4 plateau of quantum spin dimer system NH4CuCl3
复制标题
量子自旋二聚体系统 NH4CuCl3 1/4 平台周围的高场 1H-NMR 研究
DOI：
10.1088/1742-6596/828/1/012011
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
R. Scheuermann and T. Goto
中科院分区：
文献类型：
--
作者：
K. Matsui;M. Fujisawa;H. Tanaka;R. Scheuermann and T. Goto
研究了S= 1/2三维自旋二聚体NH 4CuCl 3的高场TF-μSR和1H-NMR谱，在零场下，该体系在TN = 1.29K处具有磁有序性，在高场区HC 1 = 5. 0 T-HC 2 = 12.8T和HC 3 = 17. 9 T-HC 4 = 24.7T处存在两个阶梯平台.这两个探针显示包含对应于不同的超精细场的多个峰的光谱，表明在一个晶胞中存在磁性不等价的二聚体。在斜态场H<HC 1区，部分NMR峰的分裂证实了磁有序的存在。NMR和µSR谱的整体宽度随电场的增加而增加，在H C1处没有观察到它们的轮廓发生剧烈变化。这表明自旋态的变化在进入平台态时是连续的，并且在相边界处没有发生磁振子的液-固转变。
We have investigated high-field TF-µSR and 1 H-NMR on the S= 1/2 three dimensional spin dimer system NH 4 CuCl 3, which shows a magnetic order at T N= 1.29 K under zero field and the two-stepped plateaus in high field regions H C1= 5.0 T-H C2= 12.8 T and H C3= 17.9 T-H C4= 24.7 T. Both probes showed spectra containing multiple peaks corresponding to different hyperfine fields, demonstrating the existence of magnetically inequivalent dimers in a unit cell. In the slope-state field region H< H C1, the existence of magnetic order was confirmed by the splitting in some of the NMR peaks. The whole width of NMR and µSR spectra increased with increasing field, and no drastic change in their profile was observed at H C1. This indicates that the change in the spin state is continuous on entering the plateau state, and that no liquid-solid transition of magnons takes place at the phase boundary.