Abstract
In this work, we resolve conflicting experimental and theoretical
findings related to the dynamical stability and superconducting
properties of Fm3m-LuH3,
which was recently suggested as the parent phase harboring
room-temperature superconductivity at near-ambient pressures. Including
temperature and quantum anharmonic lattice effects in our calculations,
we demonstrate that the theoretically predicted structural instability
of the Fm3m-phase near ambient pressures is suppressed for temperatures above 200 K. We provide a p–T phase diagram for stability up to pressures of 6 GPa, where the required temperature for stability is reduced to T > 80 K. We also determine the superconducting critical temperature Tc of Fm3m-LuH3
within the Migdal-Eliashberg formalism, using temperature- and
quantum-anharmonically-corrected phonon dispersions, finding that the
expected Tc for electron-phonon mediated
superconductivity is in the range of 50–60 K, i.e., well below the
temperatures required to stabilize the lattice. When considering
moderate doping based on rigidly shifting the Fermi level, Tc
decreases for both hole and electron doping. Our results thus provide
evidence that any observed room-temperature superconductivity in pure or
doped Fm3m-LuH3, if confirmed, cannot be explained by a conventional electron-phonon mediated pairing mechanism.
Originalsprache | englisch |
---|---|
Aufsatznummer | 441 |
Fachzeitschrift | Nature Communications |
Jahrgang | 15 |
Ausgabenummer | 1 |
DOIs | |
Publikationsstatus | Elektronische Veröffentlichung vor Drucklegung. - 10 Jan. 2024 |
ASJC Scopus subject areas
- Allgemeine Physik und Astronomie
- Allgemeine Chemie
- Allgemeine Biochemie, Genetik und Molekularbiologie