One of the fundamental facts of condensed matter physics is that sufficient amount of disorder always turns a Fermi-liquid metal into an Anderson insulator: a compressible but nonconducting phase of matter. Recently, topological semimetals have emerged as another way a metallic phase may be realized. In this paper we point out that, unlike ordinary metals, at least some topological semimetals are immune to localization, provided certain conditions are satisfied. We present several physical arguments, based on diagrammatic perturbation theory and Keldysh field theory, as well as decorated domain wall construction, to back up this claim.

中文翻译：

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外尔半金属缺乏本地化

凝聚态物理的基本事实之一是，足够数量的无序总是会将费米液态金属变成安德森绝缘体：物质的可压缩但不导电的相。最近，拓扑半金属作为实现金属相的另一种方式出现。在本文中，我们指出，与普通金属不同，只要满足某些条件，至少某些拓扑半金属不受局域化影响。我们基于图解微扰理论和凯尔迪什场论以及装饰域墙构造提出了几个物理论据来支持这一主张。