Lower pressure phases and metastable states of superconducting photo-induced carbonaceous sulfur hydride

G. Alexander Smith; Ines E. Collings; Elliot Snider; Dean Smith; Sylvain Petitgirard; Jesse Smith; Melanie White; Elyse Jones; Paul Ellison; Keith V. Lawler; Ranga P. Dias; Ashkan Salamat

arXiv · 2111.15051

Lower pressure phases and metastable states of superconducting photo-induced carbonaceous sulfur hydride

G. Alexander Smith·Ines E. Collings·Elliot Snider·Dean Smith·Sylvain Petitgirard·Jesse Smith·Melanie White·Elyse Jones·Paul Ellison·Keith V. Lawler·Ranga P. Dias·Ashkan Salamat

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Abstract

Room-temperature superconductivity was recently discovered in carbonaceous sulfur hydride (C-S-H) close to 3\,Mbar. We report significant differences in the superconducting response of C-S-H, with a maximum $T_{C}$ of 191(1)\,K, below a 1\,Mbar. Variations in intensity of the C-H Raman modes reveal carbon content can vary between crystals synthesized with the same photo-induced method. Synchrotron single crystal x-ray diffraction identifies polymorphism with increasing degrees of covalency. These unique metastable states are highly sensitive to thermodynamic pathways.

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G. Alexander Smith, Ines E. Collings, Elliot Snider, Dean Smith, Sylvain Petitgirard, Jesse Smith, Melanie White, Elyse Jones, Paul Ellison, Keith V. Lawler, Ranga P. Dias, Ashkan Salamat. 2021-11-30. Lower pressure phases and metastable states of superconducting photo-induced carbonaceous sulfur hydride. https://arxiv.org/abs/2111.15051

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