Compressed H<sub>3</sub>S: Fits to the Empirical <i>H<sub>c2</sub>(T)</i> Data and a Discussion of the Meissner Effect

Abstract

Based on μ-, Tand H-dependent pairing and number equations and the premise that μ(T) is predominantly the cause of the variation of the upper critical field H c2 (T), where μ, T and H denote the chemical potential, temperature and the applied field, respectively, we provide in this paper fits to the empirical H c2 (T) data of H 3 S reported by Mozaffari, et al. ( 2019) and deal with the issue of whether or not H 3 S exhibits the Meissner effect. Employing a variant of the template given by Dogan and Cohen (2021), we examine in detail the results of Hirsch and Marsiglio (2022) who have claimed that H 3 S does not exhibit the Meissner effect and Minkov, et al. (2023) who have claimed that it does. We are thus led to suggest that monitoring the chemical potential (equivalently, the number density of Cooper pairs N s at T = T c ) should shed new light on the issue being addressed.