Abstract

A new area of record superconductivity has been heralded by the discovery of superconductivity at 200 K in sulphur hydride SH3 in 2015 [1]. Since the initial discovery, further superconductors with transition temperatures up to 288 K have been reported in LaH10, YH9 , and carbonaceous sulphur hydride [2–4]. Experimental studies of the superconductivity in hydride superconductors have only been reported by a hand full of groups owing to the enormous challenges to conduct experiments at pressures above 100 GPa in diamond anvil pressures cells. Here, I will present our recent experimental results on superconductivity in SH3 , LaH4, and YH4 . Our results provide the first independent confirmation of superconductivity in SH3 . I will discuss results of detailed transport studies including in very high magnetic fields. We find forms of the critical field that suggest a strong electron-phonon coupling and multiband superconductivity in some of the hydride superconductors. I will discuss our unique experimental approach using thin-film techniques [5] in the preparation of samples for high-pressure studies and how these might allow further studies and potentially applications of hydride superconductivity.

[1] Drozdov, A. P. et al. Nature 525, 73 (2015).

[2] Somayazulu, M. et al. Phys. Rev. Lett. 122, 027001 (2019).

[3] Snider, E. et al. Nature 586, 373–377 (2020).

[4] Kong, P. et al. Nature Communications 12, 5075 (2021).

[5] Buhot, J. et al. Phys. Rev. B 102 , 104508 (2020).