Design and Synthesis of Clathrate LaB8 with Superconductivity
arXiv:2109.02313 · doi:10.1103/PhysRevB.104.174112
Abstract
Boron-based clathrate materials, typically with three-dimensional networks of B atoms, have tunable properties through substitution of guest atoms, but the tuning of B cages themselves has not yet been developed. By combining crystal structural search with the laser-heated diamond anvil cell technique, we successfully synthesized a new B-based clathrate boride, LaB8, at ~108 GPa and ~2100 K. The novel structure has a B-richest cage, with 26 B atoms encapsulating a single La atom. LaB8 demonstrates phonon-mediated superconductivity with an estimated transition temperature of 14 K at ambient pressure, mainly originating from electron-phonon coupling of B cage. This work creates a prototype platform for subsequent investigation on tunable electronic properties through the choice of captured atoms.
References in corpus (10)
- Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
- CALYPSO: a method for crystal structure prediction
- Crystal Structure Prediction via Particle Swarm Optimization
- Ionic high-pressure form of elemental boron
- Superconductivity of MgB2: Covalent Bonds Driven Metallic
- Anomalous high-temperature superconductivity in YH
- Superconductivity to 262 kelvin via catalyzed hydrogenation of yttrium at high pressures
- Stability of 41 metal - boron systems at 0 GPa and 30 GPa from first principles
- Superconductivity and Equation of State of Distorted fcc-Lanthanum above Megabar Pressures
- Pressure-induced high-temperature superconductivity retained at ambient