Based on μ-, T- and H-dependent pairing and number
equations and the premise that μ(T) is predominantly the cause of the variation of the upper critical field Hc2(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 Hc2(T) data of H3S reported by Mozaffari,et al. (2019) and deal with the issue of
whether or not H3S 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 H3S 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 Ns at T = Tc) should shed new light on the issue being
addressed.
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