近日，德国马克斯普朗克化学研究所Feng Du团队研究了隧穿光谱法测量H₃S超导间隙。2025年4月23日出版的《自然》杂志发表了这项成果。

目前已经发现几种富氢超导体显示出前所未有的高临界温度，这刺激了对这些材料超导性质的研究。尽管它们的宏观超导特性已经确立，但对配对机制的微观见解尚不清楚。研究组通过进行隧道光谱测量来表征高温超导体H₃S及其氘对应物D₃S中的超导能隙结构。

隧穿光谱表明，H₃S和D₃S都具有完全带隙结构，这可以用单个s波Dynes模型很好地描述，带隙值2Δ分别约为60 meV和44 meV。此外，研究组在合成较差的硫化氢样品中观察到另一种可能的氢贫化H_xS超导相的间隙特征。该工作从微观角度为富氢超导体H₃S的超导性提供了直接的实验证据。它验证了声子介导的超导配对机制，并为进一步了解富氢化合物高温超导性的起源奠定了基础。

附：英文原文

Title: Superconducting gap of H3S measured by tunnelling spectroscopy

Author: Du, Feng, Drozdov, Alexander P., Minkov, Vasily S., Balakirev, Fedor F., Kong, Panpan, Smith, G. Alexander, Yan, Jiafeng, Shen, Bin, Gegenwart, Philipp, Eremets, Mikhail I.

Issue&Volume: 2025-04-23

Abstract: Several hydrogen-rich superconductors have been found to show unprecedentedly high critical temperatures1,2,3,4, stimulating investigations into the nature of the superconductivity in these materials. Although their macroscopic superconducting properties are established1,5,6,7, microscopic insights into the pairing mechanism remains unclear. Here we characterize the superconducting gap structure in the high-temperature superconductor H3S and its deuterium counterpart D3S by performing tunnelling spectroscopy measurements. The tunnelling spectra reveal that H3S and D3S both have a fully gapped structure, which could be well described by a single s-wave Dynes model, with gap values 2Δ of approximately 60meV and 44meV, respectively. Furthermore, we observed gap features of another likely H-depleted HxS superconducting phase in a poorly synthesized hydrogen sulfide sample. Our work offers direct experimental evidence for superconductivity in the hydrogen-rich superconductor H3S from a microscopic perspective. It validates the phonon-mediated mechanism of superconducting pairing and provides a foundation for further understanding the origins of high-temperature superconductivity in hydrogen-rich compounds.

DOI: 10.1038/s41586-025-08895-2

Source: https://www.nature.com/articles/s41586-025-08895-2