Abstract:
Hydrides have long been considered excellent materials with traditional phonon-mediated superconductivity, providing a reliable path to room-temperature superconductors. In this study, the structural stability and superconducting properties of binary Sc
4H and Y
4H systems under ambient pressure were investigated by first principles calculations. The results show that both
Pm-3m-Sc
4H and
Pm-3m-Y
4H have van Hove singularities at Fermi level under ambient pressure, and the electron-phonon coupling intensities are significantly enhanced, resulting in superconducting transition temperatures of 1.76 K and 2.20 K. It is found that effectively suppressing the vibration frequency of hydrogen atom can reduce the theoretical synthesis pressure of hydride to a certain extent. The discovery of
Pm-3m-Sc
4H and
Pm-3m-Y
4H superconducting materials under environmental pressure greatly enriched the types of superconducting materials under environmental pressure, and provided a theoretical basis for the subsequent exploration of hydride superconducting materials.