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摘要翻译：
我们研究了适用于稀磁化合物LiHo_{x}Y_{1-x}f_4的具有局域交换作用的有效长程伊辛偶极子模型。我们的计算得到最近邻交换相互作用的值为0.12K。用Monte Carlo方法计算了铁磁相和顺磁相之间的相界T_c(x)。我们证明了实验观察到的T_c随稀释的线性下降不是简单的平均场结果，而是涨落、交换相互作用和超精细耦合效应的综合结果。此外，我们还找到了一个临界稀释度x_c=0.21(2)，低于这个临界稀释度就没有排序了。与最近在类似模型上的蒙特卡罗模拟一致，我们在计算中没有发现实验观察到的玻璃态冻结的证据。我们将Stephen和Aharony的理论应用于LiHo_{x}Y_{1-x}F_4中，发现该理论确实预言了自旋玻璃的有限温度冻结。讨论了产生差异的原因。
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英文标题：
《Phase diagram of the dilute magnet LiHo_xY_{1-x}F_4》
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作者：
A. Biltmo and P. Henelius
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最新提交年份：
2007
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分类信息：
一级分类：Physics 物理学
二级分类：Statistical Mechanics 统计力学
分类描述：Phase transitions, thermodynamics, field theory, non-equilibrium phenomena, renormalization group and scaling, integrable models, turbulence
相变，热力学，场论，非平衡现象，重整化群和标度，可积模型，湍流
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一级分类：Physics 物理学
二级分类：Disordered Systems and Neural Networks 无序系统与神经网络
分类描述：Glasses and spin glasses; properties of random, aperiodic and quasiperiodic systems; transport in disordered media; localization; phenomena mediated by defects and disorder; neural networks
眼镜和旋转眼镜；随机、非周期和准周期系统的性质；无序介质中的传输；本地化；由缺陷和无序介导的现象；神经网络
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英文摘要：
We study the effective long-range Ising dipole model with a local exchange interaction appropriate for the dilute magnetic compound LiHo_{x}Y_{1-x}F_4. Our calculations yield a value of 0.12 K for the nearest neighbor exchange interaction. Using a Monte Carlo method we calculate the phase boundary T_c(x) between the ferromagnetic and paramagnetic phases. We demonstrate that the experimentally observed linear decrease in T_c with dilution is not the simple mean-field result, but a combination of the effects of fluctuations, the exchange interaction and the hyperfine coupling. Furthermore, we find a critical dilution x_c=0.21(2), below which there is no ordering. In agreement with recent Monte Carlo simulations on a similar model, we find no evidence of the experimentally observed freezing of the glassy state in our calculation. We apply the theory of Stephen and Aharony to LiHo_{x}Y_{1-x}F_4 and find that the theory does predict a finite-temperature freezing of the spin glass. Reasons for the discrepancies are discussed.
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PDF链接：
https://arxiv.org/pdf/704.3656
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