Superconductivity of thulium substituted clathrate hexahydrides at moderate pressure

Abstract

Abstract Due to the BCS theory, hydrogen, the lightest element, would be the prospect of room-temperature superconductor after metallization, but because of the difficulty of the hydrogen metallization, the theory about hydrogen pre-compression was proposed that the hydrogen-rich compounds could be a great option for the high T c superconductors. The superior properties of TmH6, YbH6 and LuH6 indicated the magnificent potential of heavy rare earth elements for low-pressure stability. Here, we designed XTmH12 (X = Y, Yb, Lu, and La) to obtain higher T c while maintaining low pressure stability. Most prominently, YbTmH12 can stabilize at a pressure of 60 GPa. Compared with binary TmH6 hydride, its T c was increased to 48 K. The results provide an effective method for the rational design of moderate pressure stabilized hydride superconductors.

Keywords

• Hydrides
• High pressure
• Superconductivity
• First principles calculation