Phonon-mode specific contributions to room-temperature superconductivity in atomic hydrogen at high pressures

TL;DR

This study identifies specific phonon modes, particularly $E_u$, as key contributors to achieving room-temperature superconductivity in atomic hydrogen under high pressure, highlighting the importance of mode symmetry in superconductivity.

Contribution

It demonstrates that $E_u$ phonon modes are the primary drivers of high critical temperatures in atomic hydrogen at high pressures, using anisotropic Migdal-Eliashberg theory with ab initio calculations.

Findings

$E_u$ phonon modes dominate the electron-phonon coupling.

Transition temperature increases from 400 to 600 GPa despite reduced total coupling.

Enhanced $E_u$ contribution explains the increased $T_c$ at higher pressure.

Abstract

We investigate the role of specific phonon mode symmetries for the room temperature superconductivity in atomic hydrogen under large pressure. Using anisotropic Migdal-Eliashberg theory with ab initio input from density functional theory, we show that the $E_u$ phonon modes are the dominant driving force for obtaining such high critical temperatures. When going from 400 to 600 GPa, we find an increased transition temperature, however, the total electron-phonon coupling strength is counterintuitively reduced. Our analysis reveals that this is due to an enhanced contribution to the coupling strength by the $E_u$ phonon mode.