Metal Borohydrides as high-$T_c$ ambient pressure superconductors

Abstract

The extreme pressures required to stabilize the recently discovered superhydrides represent a major obstacle to their practical application. In this paper, we propose a novel route to attain high-temperature superconductivity in hydrides at ambient pressure, by doping commercial metal borohydrides. Using first-principles calculations based on Density Functional Theory and Migdal-Eliashberg theory, we demonstrate that in Ca(BH${}_4$)${}_2$ a moderate hole doping of 0.03 holes per formula unit, obtained through a partial replacement of Ca with monovalent K, is sufficient to achieve $T_c$'s as high as 110 K. The high-$T_c$ arises because of the strong electron-phonon coupling between the B-H $\sigma$ molecular orbitals and bond-stretching phonons. Using a random sampling of large supercells to estimate the local effects of doping, we show that the required doping can be achieved without significant disruption of the electronic structure and at moderate energetic cost. Given the wide commercial availability of metal borohydrides, the ideas presented here can find prompt experimental confirmation. If successful, the synthesis of high-$T_c$ doped borohydrides will represent a formidable advancement towards technological exploitation of conventional superconductors.

arXiv comment6 pages, 5 figures, submitted to APS. Supplemental material will be available upon publication

References in corpus (29)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Phonons and related properties of extended systems from density-functional perturbation theory
• Advanced capabilities for materials modelling with Quantum ESPRESSO
• Optimized norm-conserving Vanderbilt pseudopotentials
• Conventional superconductivity at 203 K at high pressures
• Superconductivity at 250 K in lanthanum hydride under high pressures
• Evidence for superconductivity above 260 K in lanthanum superhydride at megabar pressures
• Superconductivity of metallic boron in MgB_2
• Superconductivity in diamond
• Crystal Structure of 200 K-Superconducting Phase of Sulfur Hydride System
• A Perspective on Conventional High-Temperature Superconductors at High Pressure: Methods and Materials
• Anomalous high-temperature superconductivity in YH${}_6$
• Superconductivity at 161 K in Thorium Hydride $Th{H}_{10}$: Synthesis and Properties
• High-Temperature Superconductivity in Cerium Superhydrides
• Superconducting hydrides under pressure
• Design Principles for High Temperature Superconductors with Hydrogen-based Alloy Backbone at Moderate Pressure
• Three-dimensional MgB${}_2$-type superconductivity in hole-doped diamond
• Doped graphane: a prototype high-Tc electron-phonon superconductor
• Prediction of High Tc Superconductivity in Hole-doped LiBC
• LaBH${}_8$: the first high-T${}_c$ low-pressure superhydride
• Hydrogen-induced high-temperature superconductivity in two-dimensional materials: Example of hydrogenated monolayer MgB${}_2$
• In-silico synthesis of lowest-pressure high-$T_{\text{c}}$ ternary superhydrides
• High-T${}_c$ Superconductivity in doped boron-carbon clathrates
• Phase Diagram and Superconductivity of Calcium Borohyrides at Extreme Pressures
• Vibrational spectrum and electron-phonon coupling of doped solid picene from first principles
• The road to room-temperature conventional superconductivity
• Hot Hydride Superconductivity above 550 K
• High-Temperature Conventional Superconductivity in the Boron-Carbon system: Material Trends
• Local and non-local electron-phonon couplings in K3Picene and the effect of metallic screening

Cited by in corpus (9)

• Search for ambient superconductivity in the Lu-N-H system
• First-principles study on the electronic structure of Pb${}_{10-x}$Cu${}_x$(PO${}_4$)${}_6$O ($x$=0, 1)
• Effect of nitrogen doping and pressure on the stability of LuH${}_3$
• Full-bandwidth anisotropic Migdal-Eliashberg theory and its application to superhydrides
• On parent structures of near-ambient nitrogen-doped lutetium hydride superconductor
• Stabilizing a hydrogen-rich superconductor at 1 GPa by the charge-transfer modulated virtual high-pressure effect
• Assessing the feasibility of near-ambient conditions superconductivity in the Lu-N-H system
• Ab initio modeling of superconducting alloys
• HTSC-2025: A Benchmark Dataset of Ambient-Pressure High-Temperature Superconductors for AI-Driven Critical Temperature Prediction