Search for thermodynamically stable ambient-pressure superconducting hydrides in GNoME database

Abstract

Hydrides are considered to be one of the most promising families of compounds for achieving high temperature superconductivity. However, there are very few experimental reports of ambient-pressure hydride superconductivity, and the superconducting critical temperatures ($T_{\mathrm{c}}$) are typically less than 10 K. At the same time several hydrides have been predicted to exhibit superconductivity around 100 K at ambient pressure but in thermodynamically unfavorable phases. In this work we aim at assessing the superconducting properties of thermodynamically stable hydride superconductors at room pressure by investigating the GNoME material database, which has been recently released and includes thousands of hydrides thermodynamically stable at 0K. To scan this large material space we have adopted a multi stage approach which combines machine learning for a fast initial evaluation and cutting edge ab initio methods to obtain a reliable estimation of ($T_{\mathrm{c}}$). Ultimately we have identified 25 cubic hydrides with ($T_{\mathrm{c}}$) above 4.2~K and reach a maximum ($T_{\mathrm{c}}$) of 17 K. While these critical temperatures are modest in comparison to some recent predictions, the systems where they are found, being stable, are likely to be experimentally accessible and of potential technological relevance.

11 pages, 5 figures in main text

References in corpus (27)

• Restoring the density-gradient expansion for exchange in solids and surfaces
• Generalized gradient approximation for solids and their surfaces
• The PseudoDojo: Training and grading a 85 element optimized norm-conserving pseudopotential table
• Superconductivity at 250 K in lanthanum hydride under high pressures
• Evidence for superconductivity above 260 K in lanthanum superhydride at megabar pressures
• A Universal Graph Deep Learning Interatomic Potential for the Periodic Table
• Atomistic Line Graph Neural Network for Improved Materials Property Predictions
• A Perspective on Conventional High-Temperature Superconductors at High Pressure: Methods and Materials
• Anharmonic free energies and phonon dispersions from the stochastic self-consistent harmonic approximation: application to platinum and palladium hydrides
• FermiSurfer: Fermi-surface viewer providing multiple representation schemes
• Quantum Crystal Structure in the 250 K Superconducting Lanthanum Hydride
• Electronic Structure, Electron-Phonon Coupling, and Multiband Effects in MgB2
• Second order structural phase transitions, free energy curvature, and temperature-dependent anharmonic phonons in the self-consistent harmonic approximation: theory and stochastic implementation
• Superconducting properties of MgB2 from first principles
• Feasible route to high-temperature ambient-pressure hydride superconductivity
• Pressure and stress tensor of complex anharmonic crystals within the stochastic self-consistent harmonic approximation
• Prediction of Ambient Pressure Conventional Superconductivity above 80K in Thermodynamically Stable Hydride Compounds
• Superconducting pairing mediated by spin-fluctuations from first principles
• Pressure-induced high-temperature superconductivity retained at ambient
• Structure, Stability and Superconductivity of N-doped Lutetium Hydrides at kbar Pressures
• Al-Based Few-Hydrogen Metal-Bonded Perovskite High-$T_c$ Superconductor Al${}_4$H up to 54 K under Atmospheric Pressure
• Role of Coulomb interaction in the superconducting properties of CaC6 and H under pressure
• Prediction of ambient pressure superconductivity in cubic ternary hydrides with MH${}_6$ octahedra
• Superconducting Chevrel phase PbMo${}_6$S${}_8$ from first principles
• Coulomb interactions and conventional superconductivity: when going beyond the random phase approximation is essential
• Effect of spin fluctuations on superconductivity in V and Nb: a first-principles study
• High-Tc superconductivity above 130 K in cubic MH4 compounds at ambient pressure