Quantum structural fluxion in superconducting lanthanum polyhydride.

ABSTRACT: The discovery of 250-kelvin superconducting lanthanum polyhydride under high pressure marked a significant advance toward the realization of a room-temperature superconductor. X-ray diffraction (XRD) studies reveal a nonstoichiometric LaH_9.6 or LaH_10±δ polyhydride responsible for the superconductivity, which in the literature is commonly treated as LaH₁₀ without accounting for stoichiometric defects. Here, we discover significant nuclear quantum effects (NQE) in this polyhydride, and demonstrate that a minor amount of stoichiometric defects will cause quantum proton diffusion in the otherwise rigid lanthanum lattice in the ground state. The diffusion coefficient reaches ~10^-7 cm²/s in LaH_9.63 at 150 gigapascals and 240 kelvi

SUBMITTER: Wang H 

PROVIDER: S-EPMC10039887 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature