Enhanced superconductivity in CuH2 monolayers

Article

关键词: PHONON-MEDIATED SUPERCONDUCTIVITY;    TEMPERATURE;    TRANSITION;    LANTHANUM;    EXCHANGE;    HYDROGEN;    HYDRIDE;    BORIDE;    PHASE;   

DOI  :  10.1103/PhysRevB.106.014514

来源: SCIE

【 摘 要 】

Achieving superconductivity in hydrides at lower pressures is a long-standing scientific challenge. Here, we propose that reducing their effective dimensionality might be a possible route to achieve this goal. First-principles structural search calculations identify several two-dimensional transition metal hydrides (TMHs) with phonon-mediated superconductivity. Among them, the two CuH2 phases with P-3m1 and P-6m2 symmetries are predicted to have the highest T-c values up to 44.4 and 47.8 K, comparable to the well-known MgB2 superconductor. Their superconductivity mainly originates from the coupling of Cu 3d(xz)/d(yz) and H-1s electrons with in-plane H-vibrational phonons. Interestingly, both CuH2 structures show a unique superconducting energy gap by solving the anisotropic Eliashberg equations. Furthermore, the superconductivity of TMHs is closely related to the polarity of the TM-H bond. Our paper paves the way for finding hydride superconductors in low-dimensional materials.

【 授权许可】

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