Design of moderate-pressure superconductivity in a ternary hydride system

Abstract

Hydrides hold great promise for realizing high-temperature superconductivity, which is a great challenge to achieve at ambient pressure. Here, we perform high-throughput calculations to screen the superconductivity in a ternary hydride system A–B–H (A = Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba; B = Sc, Y, La, Ti, Zr, Hf, Sr, Ba, Rb, Cs) within an A15-type or perovskite framework. The results reveal that 53 of these compounds are predicted to remain dynamically stable at pressures, as low as 0, 10, and 50 GPa. Additionally, LiTiH₆, LiZrH₆, and LiHfH₆ were found to have higher critical temperatures (T_c) than that of liquid nitrogen at a low pressure of 50 GPa. The current findings identified a series of stable ternary superconducting candidates at lower pressure, facilitating the future realizations of moderate-pressure high-temperature superconductivity in hydrides.