凝聚态物理学的新篇章--超越朗道范式的拓扑量子物态  

New chapters of condensed matter physics--topological quantum phases of matter beyond the Landau-Ginzburg-Wilson paradigm

作　　者：张广铭[1] 朱国毅 ZHANG Guang-Ming;ZHU Guo-Yi(Department of Physics,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学物理系,北京100084

出　　处：《物理》2021年第9期569-582,共14页Physics

摘　　要：在凝聚态物理学发展历程中,朗道-金兹堡相变理论奠定了人们对物质形态和有序相及其相变的认识基础,在结合了威尔逊重正化群理论后,形成了朗道-金兹堡-威尔逊范式,并成为整个现代物理学宏伟大厦的重要基石。然而,在复杂电子多体系统的实验研究中,以量子霍尔效应、分数量子霍尔效应和铜氧化物高温超导体的实验发现为代表,涌现了众多超越朗道-金兹堡-威尔逊范式的新奇量子物态,掀开了凝聚态物理学的新篇章。文章从量子霍尔效应出发,介绍了二维电子体系中的几种典型拓扑量子物态。之后,重点介绍二维强关联电子多体系统中的内禀拓扑有序态。围绕Kitaev提出的二维Toric Code量子自旋模型,详细论证了该模型的基态为具有Z_(2)内禀拓扑序的量子自旋液体,讨论了其基态的拓扑简并、低能任意子激发,以及相关的拓扑量子相变。同时,简要介绍了内禀拓扑有序态的最新研究进展和可能的未来发展方向。In the history of condensed matter physics, the Landau―Ginzburg continuous phase transition theory provided the understanding of the condensed ordered phases and their related phase transitions. Combined with the Wilson renormalization group theory, the Landau―Ginzburg―Wilson paradigm finally became the cornerstone of modern physics.However, since the discoveries of the quantum Hall effect, fractional quantum Hall effect, and higher temperature copper-oxide superconductors, there emerged more and more exotic quantum phases of matter beyond the Landau―Ginzburg―Wilson paradigm, opening new chapters of condensed matter physics. In this article, we briefly review the basic physics of several important topological quantum phases based on the integer quantum Hall effect of twodimensional electron systems. Then we focus on intrinsic topologically ordered phases of matter in two-dimensional strongly correlated electron systems. In particular, for the toric code model proposed by Kitaev for quantum computation, we discuss its topological ordered wave functions, ground-state degeneracy, topological anyonic excitations, and the possible topological quantum phase transitions. In addition, we outline some recent important theoretical progresses and possible future directions.

关 键 词：朗道连续相变 拓扑量子物态 量子自旋液体 拓扑量子相变 

分 类 号：O469[理学—凝聚态物理]