Theoretical Prediction of High-Temperature Superconductivity in SrAuH$_3$ at Ambient Pressure

TL;DR

This study predicts that certain hydride compounds, specifically SrAuH$_3$ and SrZnH$_3$, could be ambient-pressure superconductors with critical temperatures over 100 K, challenging the belief that high-$T_c$ hydrides need high pressures.

Contribution

The paper introduces a computational approach identifying stable hydrides that are predicted to be high-temperature superconductors at ambient pressure, a significant advancement over previous pressure-dependent findings.

Findings

SrAuH$_3$ and SrZnH$_3$ predicted to have $T_c$ > 100 K at ambient pressure

Electronic structure analysis highlights the dominant role of the $X$ component in superconductivity

Identification of 17 dynamically stable hydride compounds

Abstract

We present a comprehensive computational investigation of electron-phonon interactions in MXH$_3$ hydride compounds, where $M$ represents alkali and post-transition metals, and $X$ denotes 3$d$, 4$d$, and 5$d$ transition metals. Our density functional theory calculations identify 17 dynamically stable compounds. Notably, SrAuH$_3$ and SrZnH$_3$ emerge as theoretical ambient-pressure superconductors with predicted critical temperatures ($T_c$) exceeding 100 K. Analysis of the electronic structure reveals that the $X$ component dominates the density of states at the Fermi level, playing a crucial role in determining electron-phonon coupling strength and superconducting properties. We elucidate the underlying mechanisms governing these properties through detailed examination of the electronic and vibrational spectra. Our findings may challenge the prevailing notion that high-$T_c$ superconductivity in hydrides requires extreme pressures, potentially paving the way for practical applications. This study also provides valuable insights to guide future experimental efforts in the synthesis of ambient-pressure hydride superconductors.