Comparison of highly-compressed <i>C</i> 2/ <i>m</i> -SnH <sub>12</sub> superhydride with conventional superconductors
E. F. Talantsev
Abstract
Abstract Satterthwaite and Toepke (1970 Phys. Rev. Lett. 25 741) predicted high-temperature superconductivity in hydrogen-rich metallic alloys, based on an idea that these compounds should exhibit high Debye frequency of the proton lattice, which boosts the superconducting transition temperature, T c . The idea has got full confirmation more than four decades later when Drozdov et al (2015 Nature 525 73) experimentally discovered near-room-temperature superconductivity in highly-compressed sulphur superhydride, H 3 S. To date, more than a dozen of high-temperature hydrogen-rich superconducting phases in Ba–H, Pr–H, P–H, Pt–H, Ce–H, Th–H, S–H, Y–H, La–H, and (La, Y)–H systems have been synthesized and, recently, Hong et al (2021 arXiv :2101.02846) reported on the discovery of C 2/ m -SnH 12 phase with superconducting transition temperature of T c ∼ 70 K. Here we analyse the magnetoresistance data, R ( T , B ), of C 2/ m -SnH 12 phase and report that this superhydride exhibits the ground state superconducting gap of Δ(0) = 9.2 ± 0.5 meV, the ratio of 2Δ(0)/ k B T c = 3.3 ± 0.2, and 0.010 < T c / T F < 0.014 (where T F is the Fermi temperature) and, thus, C 2/ m -SnH 12 falls into unconventional superconductors band in the Uemura plot.