High-Temperature Superconductivity in Doped Boron Clathrates

The recent discoveries of near-room-temperature superconductivity in clathrate hydrides present compelling evidence for the reliability of theory-orientated conventional superconductivity. Nevertheless, the harsh pressure conditions required to maintain such high T c limit their practical applications. To address this challenge, we conducted extensive first-principles calculations to investigate the doping effect of the recently synthesized LaB8 clathrate, intending to design high-temperature superconductors at ambient pressure. Our results demonstrate that these clathrates are highly promising for high-temperature superconductivity owing to the coexistence of rigid boron covalent networks and the tunable density of states at the Fermi level. Remarkably, the predicted T c of BaB8 could reach 62K at ambient pressure, suggesting a significant improvement over the calculated T c of 14K in LaB8. Moreover, further calculations of the formation enthalpies suggest that BaB8 could be potentially synthesized under high-temperature and high-pressure conditions. These findings highlight the potential of doped boron clathrates as promising superconductors and provide valuable insights into the design of light-element clathrate superconductors.