论文标题
碳掺杂的硫磺氢化物作为270 GPA的室温超导体
Carbon-Doped Sulfur Hydrides as Room-Temperature Superconductors at 270 GPa
论文作者
论文摘要
为了理解高压碳硫硫氢（CSH）系统中室温超导性的最新实验，我们使用通用进化算法进行了广泛的化学计量和三元CSH化合物的结构搜索。根据不同CSH化合物的形成焓来判断，我们的研究得出的结论是，在各种CSH系统中，一定水平的碳掺杂（〜5％-6％）（〜5％-6％）（H $ _3 $ s）在300万兰特（H $ _3 $ s），而相位则产生了最稳定的结构（第二位于H $ _3 $ S）。碳在诸如C $ _1 $ _1 $ _1 {15} $ H $ _ {48} $和C $ _1 $ S $ _ {17} $ H $ _ {54} $中的较强的电子偶数和更高的频率的情况下，将少量的硫原子替换为碳中的少量硫原子。 〜270 GPA的超导性。计算出的超导转换温度t $ _c的c $ _1 $ _1 $ s $ _ {15} $ h $ _ {48} $和c $ _1 $ _1 $ s $ _ {17} $ h $ _ {54} $作为压力的功能，表明了与实验测量的合理良好一致性。在〜80 GPA过渡到超导状态之前，预计CSH系统具有C $ _2 $ _2 $ s $ _2 $ _2 $ h $ _ {10} $的化学计量，并具有P1对称性稳定结构的稳定结构，这是由其Raman Spectrum与实验的直接比较支持的。
To understand the most-recent experiment on room-temperature superconductivity in carbonaceous sulfur hydride (CSH) systems under high pressure, we have performed extensive stoichiometry and structure searches of ternary CSH compounds using generic evolutionary algorithms. Judged from the formation enthalpy of different CSH compounds, our studies conclude that certain levels of carbon doping (~5%-6%) in sulfur hydride (H$_3$S) in its R3m and phases gives rise to the most-stable structure (second to the H$_3$S itself) among the various CSH systems found. The replacement of a small amount of sulfur atoms by carbon in compounds like C$_1$S$_{15}$H$_{48}$ and C$_1$S$_{17}$H$_{54}$ results in a stronger electron-phonon coupling and a higher averaged phonon frequency that increases with pressure, thereby leading to room-temperature superconductivity at ~270 GPa. The calculated superconducting transition temperature T$_c$ of C$_1$S$_{15}$H$_{48}$ and C$_1$S$_{17}$H$_{54}$ as a function of pressure shows reasonably good agreement with experimental measurements. Before transition to superconducting states at ~80 GPa, the CSH system is predicted to have a stoichiometry of C$_2$S$_2$H$_{10}$ with a stable structure of P1 symmetry, which is supported by the direct comparison of its Raman spectrum with experiment.
