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
Max Planck Institute for Chemistry, Mainz, Germany.
National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM, USA.
Nature. 2025 May;641(8063):619-624. doi: 10.1038/s41586-025-08895-2. Epub 2025 Apr 23.
Several hydrogen-rich superconductors have been found to show unprecedentedly high critical temperatures, stimulating investigations into the nature of the superconductivity in these materials. Although their macroscopic superconducting properties are established, microscopic insights into the pairing mechanism remains unclear. Here we characterize the superconducting gap structure in the high-temperature superconductor HS and its deuterium counterpart DS by performing tunnelling spectroscopy measurements. The tunnelling spectra reveal that HS and DS both have a fully gapped structure, which could be well described by a single s-wave Dynes model, with gap values 2Δ of approximately 60 meV and 44 meV, respectively. Furthermore, we observed gap features of another likely H-depleted HS superconducting phase in a poorly synthesized hydrogen sulfide sample. Our work offers direct experimental evidence for superconductivity in the hydrogen-rich superconductor HS 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.
已发现几种富氢超导体呈现出前所未有的高临界温度，这激发了对这些材料中超导性本质的研究。尽管它们的宏观超导特性已得到确定，但对配对机制的微观认识仍不明确。在此，我们通过进行隧穿光谱测量来表征高温超导体HS及其氘代对应物DS中的超导能隙结构。隧穿光谱表明，HS和DS均具有完全能隙结构，这可以用单s波戴恩斯模型很好地描述，其能隙值2Δ分别约为60毫电子伏特和44毫电子伏特。此外，我们在合成不佳的硫化氢样品中观察到了另一个可能贫氢的HS超导相的能隙特征。我们的工作从微观角度为富氢超导体HS中的超导性提供了直接实验证据。它验证了超导配对的声子介导机制，并为进一步理解富氢化合物中高温超导性的起源奠定了基础。
