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Phonon-mediated high-T c superconductivity in hole-doped diamond-like crystalline hydrocarbon.

ABSTRACT: We here predict by ab initio calculations phonon-mediated high-T c superconductivity in hole-doped diamond-like cubic crystalline hydrocarbon K 4-CH (space group I21/3). This material possesses three key properties: (i) an all-sp 3 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 ?-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.

SUBMITTER: Lian CS

PROVIDER: S-EPMC5431101 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Phonon-mediated high-T c superconductivity in hole-doped diamond-like crystalline hydrocarbon.

Lian Chao-Sheng CS Wang Jian-Tao JT Duan Wenhui W Chen Changfeng C

Scientific reports 20170503 1

We here predict by ab initio calculations phonon-mediated high-T c superconductivity in hole-doped diamond-like cubic crystalline hydrocarbon K 4-CH (space group I21/3). This material possesses three key properties: (i) an all-sp 3 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 c ...[more]

PMID: 28469256

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