Anomalous behavior in high-pressure carbonaceous sulfur hydride

Mehmet Dogan; Marvin L. Cohen

doi:10.1016/j.physc.2021.1353851

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arXiv · 2012.10771

Anomalous behavior in high-pressure carbonaceous sulfur hydride

Mehmet Dogan·Marvin L. Cohen

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Abstract

A new experimental study by Snider et al. [Nature 586, 373-377 (2020)] reported behavior in a high-pressure carbon-sulfur-hydrogen system that has been interpreted by the authors as superconductivity at room temperature. The sudden drop of electrical resistance at a critical temperature and the change of the R vs. T behavior with an applied magnetic field point to superconductivity. This is a very exciting study in one of the most important areas of science, hence, it is crucial for the community to investigate these findings and hopefully reproduce these results. In this comment, we present calculations that expand upon the arguments put forth by Hirsch and Marsiglio [arXiv:2010.10307], and offer some speculations about physical mechanisms that might explain the observed data. In agreement with Hirsch and Marsiglio, we show that there are errors in the analysis presented in the experimental paper, and with the correct analysis, the reported R vs. T data significantly deviate from the expected behavior. In particular, the extremely sharp change in resistance at the superconducting transition is not consistent with a strongly type II superconductor.

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Mehmet Dogan, Marvin L. Cohen. 2020-12-19. Anomalous behavior in high-pressure carbonaceous sulfur hydride. https://doi.org/10.1016/j.physc.2021.1353851

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