Density Variation of the Frustrated Ferromagnetism in 2D Solid H^^3e
Density Variation of the Frustrated Ferromagnetism in 2D Solid H^^3e
复制标题
二维固体 H^^3e 中受抑铁磁性的密度变化
DOI：
10.1007/s10909-009-9993-9
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
and H. Fukuyama
中科院分区：
文献类型：
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作者：
D. Sato;S. Takayoshi;K. Obata;T. Matsui;and H. Fukuyama
在宽温度范围内（0.3 ≤T≤ 80 mK），测量了在石墨表面预镀~ 4 He单分子膜（~ 3 He/~ 4 He/gr）的第二层非公度固体~ 3 He吸附的热容。从高温级数展开拟合，我们得到了这种二维量子固体固有的多自旋交换相互作用的密度依赖性。与3 He/3 He/gr系统的早期结果相比，在最低密度下，有效的双自旋交换相互作用的大小明显减小，而在最高密度下几乎相同.我们认为，这种差异是由两个系统中的第二层IC固体的不同密度造成的。我们还表明，从目前的热容数据推导出的总自旋熵变小于预期值约18%。
We measured heat capacities of the second layer incommensurate (IC) solid3He adsorbed on graphite preplated with monolayer4He (3He/4He/gr) in a wide temperature range (0.3 ≤T≤ 80 mK). From the high temperature series expansion fitting, we obtained density dependences of the multiple spin exchange interactions inherent to this two-dimensional quantum solid. Compared with the earlier results for the3He/3He/gr system, the magnitude of the effective two-spin exchange interaction is clearly smaller at the lowest densities, while it is nearly the same at the highest densities. We argue that this difference is caused by the different densities of the second layer IC solids in the two systems. We also show that the total spin-entropy changes deduced from the present heat capacity data are smaller than the expected value by about 18%.