2019/12/23 by E. F. Talantsev · 1 citation
Physics and Astronomy · #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1088/1361-6668/abb11a
published as Superconductor Science and Technology 33, 124001 (2020) · 9 pages, 2 figures, 1 table. arXiv admin note: substantial text overlap with arXiv:1912.13293
arxiv created 2020/01/04 · arxiv updated 2020/10/29
Oxygen exhibits structural phase transformation from non-metallic ε-O2 phase into metallic ζ-O2 phase at pressure of P = 96 GPa (Desgreniers et al 1990 J. Phys. Chem. 94 1117; Akahama et al 1995 Phys. Rev. Lett. 74 4690). Metallic ζ-O2 phase is a superconductor with transition temperature of Tc = 0.6 K at P = 115-120 GPa (Shimizu et al 1998 Nature 393 767). In this paper we have performed analysis of temperature dependent upper critical field, Bc2(T), for ζ-O2 phase (P = 115 GPa) and show that this highly-compressed phase of gaseous molecular element is unconventional superconductor with the ratio of Tc to the Fermi temperature, Tf, in the range of 0.009 < Tc/Tf < 0.108.