Possible high-T C superconductivity at 50 GPa in sodium hydride with clathrate structure
Possible high-T C superconductivity at 50 GPa in sodium hydride with clathrate structure
复制标题
DOI：
10.1088/1367-2630/ac1df3
复制
发表时间：
2021-09-01
影响因子：
3.3
通讯作者：
Jeng, Horng-Tay
中科院分区：
文献类型：
--
作者：
Chen, Chin-Hsuan;Huang, Angus;Jeng, Horng-Tay
常压室温超导是科学的终极目标之一，因为它将在世界范围内带来各种技术的革命性变化。从理论上预测了几种超高压(大于或接近100 Gpa)的室温和近室温氢化物超导体。特别是，200 GPa时T(C)与203K相近或等于203K的硫化氢(H3S)很快被实验证实，建立了迈向室温超导的里程碑。然而，在较低气压下(小于或类似于100 Gpa)的高温(C)超导体还没有报道。在这项工作中，我们提出了在氢化钠笼状结构NaH6中，在相对较低的50 Gpa压力下，180K的高温超导电性。在100 GPa时，T(C)可以提高到206K，与H3S的T(C)相似，但压力要低得多。在200 GPa时，T(C)达到最大值210K，略高于H3S。伽马点T(2g)声子模给出的强电声子耦合强度对超导电性起着关键作用。我们的工作从理论上证明了氢化物可以在相对较低的压力下稳定下来，并具有高T(C)超导电性。
Ambient-pressure room-temperature superconductivity is one ultimate goal of science, for it will bring worldwide revolutionary changes in all kinds of technology. Several room temperature and near room temperature hydride superconductors at ultra high pressure (greater than or similar to 100 GPa) have been predicted theoretically. In particular, the hydrogen sulfide (H3S) with T (C) similar or equal to 203 K at 200 GPa has soon been confirmed experimentally, establishing a milestone toward room temperature superconductivity. However, high-T (C) superconductors at lower pressure (less than or similar to 100 GPa) have not been reported before. In this work, we present high-T (C) superconductivity of 180 K at a relatively low pressure of 50 GPa in sodium hydride clathrate structure NaH6. The T (C) can be raised up to 206 K at 100 GPa, similar to the T (C) of H3S but at a much lower pressure. At 200 GPa, it reaches the highest T (C) of 210 K, slightly higher than that of H3S. The strong electron-phonon coupling strength given by the T (2g ) phonon mode at Gamma point plays the key role in superconductivity. Our work demonstrates theoretically that hydrides could stabilize at a relatively low pressure and host high-T (C) superconductivity.