论文标题
沮丧
Frustrated Kondo impurity triangle: A simple model of deconfinement
论文作者
论文摘要
解糊精和拓扑顺序的概念对量子信息科学以及我们对量子材料的理解具有极大的兴趣。在这里，我们介绍了一个简单的模型，该模型的三个抗磁性耦合杂种杂质，即近托三角形，可用于进一步将这些概念的应用扩展到电子系统中。我们表明，通过调整磁性挫败感，近托三角形在不间断的对称性的两个阶段之间经历了量子相变，这向兰道范式以外的相变信号。我们证明，挫败的旋转液相由三通道近代（3CK）固定点描述，因此显示了非理性的基态脱落率。使用Abrikosov伪层表示，该量子状态由出现的u（1）量规场及其投射对称组进行分类。量规理论是在微型威尔逊环路命令和拓扑缺陷（量规场中的激体）被驱逐出来的意义上是脱辅理论的。在存在中等的围筛筛选的情况下，该阶段一直存在，直到拓扑缺陷的增殖导致量子相变为未腐烂的费米液相。基于此证据，我们建议3CK相显示与无间隙旋转液体相似的拓扑顺序。
The concepts of deconfinement and topological order are of great current interest for quantum information science and for our understanding of quantum materials. Here, we introduce a simple model of three antiferromagnetically coupled Kondo impurities, a Kondo triangle, which can be used to further extend the application of these concepts to electronic systems. We show that, by tuning the magnetic frustration, the Kondo triangle undergoes a quantum phase transition between two phases of unbroken symmetry, signaling a phase transition beyond the Landau paradigm. We demonstrate that the frustrated spin liquid phase is described by a three-channel Kondo (3CK) fixed point and thus displays an irrational ground state degeneracy. Using an Abrikosov pseudofermion representation, this quantum state is categorized by an emergent U(1) gauge field and its projective symmetry group. The gauge theory is deconfining in the sense that a miniature Wilson loop orders and topological defects (instantons in the gauge field) are expelled. This phase persists in the presence of moderate Kondo screening until proliferation of topological defects leads to a quantum phase transition to an unfrustrated Fermi liquid phase. Based on this evidence, we propose that the 3CK phase displays topological order in a similar sense as gapless spin liquids.
