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摘要翻译：
对于许多真正的自旋玻璃材料来说，具有连续对称自旋的爱德华兹-安德森模型比更好理解的伊辛变体更现实。原则上，这种体系中出现的自旋玻璃相的性质可以从零温性质的分析中推断出来。不幸的是，除了少数例外，基态构型的求解在计算上是一个非多项式问题，因此需要高效的近似算法。在这里，我们利用最近发展起来的遗传嵌入匹配(GEM)启发式方法研究了二维双峰XY自旋玻璃零温相的性质。我们分析了体的性质，如渐近基态能量和无序强度与无序浓度的相图。对于铁磁键和反铁磁键对称分布的情形，我们发现模型的基态是唯一的，直到自旋的整体O(2)旋转。特别是，该模型中没有广泛的退化。本文的主要工作是通过改变边界条件来研究激发谱。利用适当的有限尺寸标度技术，我们一致地确定了自旋和手征畴壁的刚度以及相应的分形维数。最值得注意的是，我们发现自旋和手征通道具有两个不同的刚度指数，因此系统在大尺度上表现出自旋-手征解耦。重叠分布的结果不支持存在大量热力学纯态的可能性。
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英文标题：
《Zero-temperature phase of the XY spin glass in two dimensions: Genetic
embedded matching heuristic》
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作者：
Martin Weigel and Michel J. P. Gingras
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最新提交年份：
2008
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分类信息：
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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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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英文摘要：
For many real spin-glass materials, the Edwards-Anderson model with continuous-symmetry spins is more realistic than the rather better understood Ising variant. In principle, the nature of an occurring spin-glass phase in such systems might be inferred from an analysis of the zero-temperature properties. Unfortunately, with few exceptions, the problem of finding ground-state configurations is a non-polynomial problem computationally, such that efficient approximation algorithms are called for. Here, we employ the recently developed genetic embedded matching (GEM) heuristic to investigate the nature of the zero-temperature phase of the bimodal XY spin glass in two dimensions. We analyze bulk properties such as the asymptotic ground-state energy and the phase diagram of disorder strength vs. disorder concentration. For the case of a symmetric distribution of ferromagnetic and antiferromagnetic bonds, we find that the ground state of the model is unique up to a global O(2) rotation of the spins. In particular, there are no extensive degeneracies in this model. The main focus of this work is on an investigation of the excitation spectrum as probed by changing the boundary conditions. Using appropriate finite-size scaling techniques, we consistently determine the stiffness of spin and chiral domain walls and the corresponding fractal dimensions. Most noteworthy, we find that the spin and chiral channels are characterized by two distinct stiffness exponents and, consequently, the system displays spin-chirality decoupling at large length scales. Results for the overlap distribution do not support the possibility of a multitude of thermodynamic pure states.
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PDF链接：
https://arxiv.org/pdf/706.0227
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