20 / 2023-03-28 16:03:57

Superconducting Li8Au electride at high pressrue

high pressure,superconductivity,electride,first-principles calculations

高压物理与材料科学 > 氢与高能量密度材料-II

  Exploring new superconductors and unveiling superconducting mechanism are significant frontiers in condensed matter physics. The superconductivity of electrides is strongly associated with the concentration and topological morphology of interstitial anionic electrons (IAEs), which adds a new dimension to the modulation of superconductivity in materials, and provides a new cognition for the extension of electron-phonon coupling mechanism.^[1-5]

  We have designed a high-symmetry NaCl-type Li₈Au electride by replacing the edge-shared Li₃ cube in Fm-3m Li₃Au with isolated IAEs-centered Li₈ cages at high pressure. In contrast to the known superconducting electrides in which interconnected IAEs are crucial for the superconducting transition, the isolated IAEs in Li₈Au, having a p-orbital attribute, strongly couple with the medium-/low-frequency vibrations of the Li₈ cages, inducing the T_c values of 68.5-81.8 K, which refreshes the superconducting transition of electrides.^[6] Our study not only adds a new important member into superconductor family, but also opens up a new design direction for electride superconductivity.Exploring new superconductors and unveiling superconducting mechanism are significant frontiers in condensed matter physics. The superconductivity of electrides is strongly associated with the concentration and topological morphology of interstitial anionic electrons (IAEs), which adds a new dimension to the modulation of superconductivity in materials, and provides a new cognition for the extension of electron-phonon coupling mechanism.^[1-5]

We have designed a high-symmetry NaCl-type Li₈Au electride by replacing the edge-shared Li₃ cube in Fm-3m Li₃Au with isolated IAEs-centered Li₈ cages at high pressure. In contrast to the known superconducting electrides in which interconnected IAEs are crucial for the superconducting transition, the isolated IAEs in Li₈Au, having a p-orbital attribute, strongly couple with the medium-/low-frequency vibrations of the Li₈ cages, inducing the T_c values of 68.5-81.8 K, which refreshes the superconducting transition of electrides.^[6] Our study not only adds a new important member into superconductor family, but also opens up a new design direction for electride superconductivity.