Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
School of Physics, University of Chinese Academy of Sciences, Beijing, 100049, China.
Sci Rep. 2017 May 3;7(1):1464. doi: 10.1038/s41598-017-01541-6.
We here predict by ab initio calculations phonon-mediated high-T superconductivity in hole-doped diamond-like cubic crystalline hydrocarbon K -CH (space group I2/3). This material possesses three key properties: (i) an all-sp covalent carbon framework that produces high-frequency phonon modes, (ii) a steep-rising electronic density of states near the top of the valence band, and (iii) a Fermi level that lies in the σ-band, allowing for a strong coupling with the C-C bond-stretching modes. The simultaneous presence of these properties generates remarkably high superconducting transition temperatures above 80 K at an experimentally accessible hole doping level of only a few percent. These results identify a new extraordinary electron-phonon superconductor and pave the way for further exploration of this novel superconducting covalent metal.
我们通过从头算预测了掺杂空穴的类金刚石立方晶态碳氢化合物 K -CH（空间群 I2/3）中的声子介导高温超导。该材料具有三个关键特性：（i）全 sp3 共价碳骨架，可产生高频声子模式；（ii）价带顶附近急剧上升的电子态密度；（iii）费米能级位于σ带中，可与 C-C 键伸缩模式进行强耦合。这些特性的同时存在，在实验上可达到仅百分之几的空穴掺杂水平时，就能产生高于 80 K 的显著高温超导转变温度。这些结果确定了一种新的非凡电子-声子超导体，并为进一步探索这种新型超导共价金属铺平了道路。
