High-temperature superconductivity up to 223 K in the Al stabilized metastable hexagonal lanthanum superhydride

Autor: Su Chen, Yingcai Qian, Xiaoli Huang, Wuhao Chen, Jianning Guo, Kexin Zhang, Jinglei Zhang, Huiqiu Yuan, Tian Cui
Rok vydání: 2023
Předmět:
Zdroj: National Science Review.
ISSN: 2053-714X
2095-5138
DOI: 10.1093/nsr/nwad107
Popis: As compressed hydrides constantly refresh the records of superconducting critical temperatures (Tc) in the vicinity of room temperature, this further reinforces the confidence to find more high-temperature superconducting hydrides. In this process, metastable phases of superhydrides offer enough possibilities to access superior superconducting properties. Here we report a metastable hexagonal lanthanum superhydride (P63/mmc-LaH10) stabilized at 146 GPa by introducing an appropriate proportion of Al, which exhibits high-temperature superconductivity with Tc ∼ 178 K, and this value is enhanced to a maximum Tc ∼ 223 K at 164 GPa. A huge upper critical magnetic field value Hc2(0) reaches 223 T at 146 GPa. The small volume expansion of P63/mmc-(La, Al) H10 compared with the binary LaH10 indicates the possible interstitial sites of Al atoms filling into the La-H lattice, instead of forming conventional ternary alloy-based superhydrides. This work provides a new strategy for metastable high-temperature superconductors through the multiple-element system.
Databáze: OpenAIRE