Quantum crystal structure in the 250-kelvin superconducting lanthanum hydride

Ion Errea, Francesco Belli, Lorenzo Monacelli, Antonio Sanna, Takashi Koretsune, Terumasa Tadano, Raffaello Bianco, Matteo Calandra, Ryotaro Arita, Francesco Mauri and José A. Flores-Livas ()
Additional contact information
Ion Errea: University of the Basque Country (UPV/EHU)
Francesco Belli: University of the Basque Country (UPV/EHU)
Lorenzo Monacelli: Università di Roma La Sapienza
Antonio Sanna: Max-Planck Institute of Microstructure Physics
Takashi Koretsune: Tohoku University
Terumasa Tadano: National Institute for Materials Science
Raffaello Bianco: Centro de Física de Materiales (CSIC-UPV/EHU)
Matteo Calandra: Sorbonne Université, CNRS, Institut des Nanosciences de Paris
Ryotaro Arita: University of Tokyo
Francesco Mauri: Università di Roma La Sapienza
José A. Flores-Livas: Università di Roma La Sapienza

Nature, 2020, vol. 578, issue 7793, 66-69

Abstract: Abstract The discovery of superconductivity at 200 kelvin in the hydrogen sulfide system at high pressures1 demonstrated the potential of hydrogen-rich materials as high-temperature superconductors. Recent theoretical predictions of rare-earth hydrides with hydrogen cages2,3 and the subsequent synthesis of LaH10 with a superconducting critical temperature (Tc) of 250 kelvin4,5 have placed these materials on the verge of achieving the long-standing goal of room-temperature superconductivity. Electrical and X-ray diffraction measurements have revealed a weakly pressure-dependent Tc for LaH10 between 137 and 218 gigapascals in a structure that has a face-centred cubic arrangement of lanthanum atoms5. Here we show that quantum atomic fluctuations stabilize a highly symmetrical $${Fm}\overline{3}{m}$$Fm3¯m crystal structure over this pressure range. The structure is consistent with experimental findings and has a very large electron–phonon coupling constant of 3.5. Although ab initio classical calculations predict that this $${Fm}\overline{3}{m}$$Fm3¯m structure undergoes distortion at pressures below 230 gigapascals2,3, yielding a complex energy landscape, the inclusion of quantum effects suggests that it is the true ground-state structure. The agreement between the calculated and experimental Tc values further indicates that this phase is responsible for the superconductivity observed at 250 kelvin. The relevance of quantum fluctuations calls into question many of the crystal structure predictions that have been made for hydrides within a classical approach and that currently guide the experimental quest for room-temperature superconductivity6–8. Furthermore, we find that quantum effects are crucial for the stabilization of solids with high electron–phonon coupling constants that could otherwise be destabilized by the large electron–phonon interaction9, thus reducing the pressures required for their synthesis.

Date: 2020
References: Add references at CitEc
Citations: View citations in EconPapers (7)

Downloads: (external link)
https://www.nature.com/articles/s41586-020-1955-z Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:578:y:2020:i:7793:d:10.1038_s41586-020-1955-z

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/s41586-020-1955-z

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().