The 6th International Conference on Matter and Radiation at Extremes (ICMRE2023)

124 / 2023-04-14 13:42:28

Hydride Superconductors Under High Pressure

high pressure,hydrides,superconductors,crystal structure

High Pressure Physics and Materials Science > Hydrogen and high-energy density material-II

Room-temperature superconductors have long been the ultimate goal of scientists. Superhydrides exhibit abundant crystal structures and electronic structures under high pressure. They are the forefront of physics, materials science and superconductivity. Recently, researchers have discovered binary H₃S and LaH₁₀ with T_c up to 203 K and 260 K, respectively. In this regard, these findings set a new record for superconductivity, a step closer to room-temperature superconductivity.

We have discovered several new binary hydride superconductors such as Ce-H, Pr-H and Ba-H with atomic and molecular hydrogen configurations by using high pressure experimental techniques. Interestingly, CeH₁₀ has a superconducting transition temperature of 115 K at 95 GPa, which is the highest one of the binary hydrides below 1 Megabar. Based on binary hydrides, we have expanded the targets to the ternary system, and found the record superconducting transition temperature in La-Ce-H system below 1 Megabar (176 GPa at 100 GPa). In addition, by introducing Al atoms, we have stabilized the metastable hexagonal phase LaH₁₀ to 146 GPa, with superconducting transition temperature reaching 223 K. These studies have not only yielded new types of hydride superconductors, but also deepened the understanding of high-temperature superconductivity in hydrides, laying a foundation for future experiments to obtain new high-temperature superconductors under mild conditions.



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