Route to high-<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>T</mml:mi><mml:mi>c</mml:mi></mml:msub></mml:math> superconductivity via <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>CH</mml:mi><mml:mn>4</mml:mn></mml:msub></mml:math>-intercalated <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi mathvariant="normal">H</mml:mi><mml:mn>3</mml:mn></mml:msub><mml:mi mathvariant="normal">S</mml:mi></mml:mrow></mml:math> hydride perovskites
Wenwen Cui, Tiange Bi, Jingming Shi, Yinwei Li, Hanyu Liu, Eva Zurek, Russell J. Hemley
Abstract
While exploring potential superconductors in the C-S-H ternary system using first-principles crystal structure prediction methods, we uncovered a class of hydride perovskites based on the intercalation of methane into an ${\mathrm{H}}_{3}\mathrm{S}$ framework. These intriguing ${\mathrm{H}}_{3}\mathrm{S}\text{\ensuremath{-}}{\mathrm{CH}}_{4}$ structures emerge as metastable at $\ensuremath{\sim}100$ GPa. Electron-phonon coupling calculations indicate that phases with ${\mathrm{CSH}}_{7}$ stoichiometry are potential superconductors with ${T}_{c}$ values ranging from 100 K to 190 K at megabar pressures. The results are expected to guide the experimental search for new high-${T}_{c}$ superconductors, including those stable at lower pressures than previously documented superconducting hydrides such as ${\mathrm{H}}_{3}\mathrm{S}$ and ${\mathrm{LaH}}_{10}$.