Abstract We present an overview of hydrogen-containing superconductors, including metallic, cuprate, pnictide and carbon-based materials. Particularly in BCS-like superconductors, hydrogen introduces new phonon modes and these may lead to better or worse superconducting properties, with anharmonicity of the H potential being a decisive factor. The availability of the deuterium isotope, in addition to protium, makes hydrogen an extremely useful extra probe of mechanisms of superconductivity. While hydrogen modification has not so far led to any confirmed remarkable improvement in already existing metallic superconductors, hydrogen plays an important role in the synthesis of novel iron-based superconductors and as a substitutional impurity appears to increase the transition temperature. Most recently, a new record for the superconducting transition temperature of 203 K has been claimed for a metallic hydride under high pressure, H 2 S. We survey elemental hydrides and superconductors, discuss techniques for introducing hydrogen into materials, then review and summarise published knowledge about hydrogen-containing superconductors.

中文翻译：

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氢改性超导体：综述

摘要 我们概述了含氢超导体，包括金属、铜酸盐、pnictide 和碳基材料。特别是在类似 BCS 的超导体中，氢引入了新的声子模式，这些可能导致更好或更差的超导特性，其中 H 电位的非谐性是决定性因素。除了氚之外，氘同位素的可用性使氢成为超导机制的一个非常有用的额外探针。虽然到目前为止，氢改性还没有对现有金属超导体产生任何可证实的显着改进，但氢在新型铁基超导体的合成中起着重要作用，并且作为替代杂质似乎会提高转变温度。最近，