Anatomy of the band structure of the newest apparent near-ambient superconductor LuH${}_{3-x}$N${}_x$

Abstract

Recently it was claimed that nitrogen-doped lutetium hydride exhibited a near-ambient superconducting transition with a temperature of 294 K at a pressure of only 10 kbar, this pressure being several orders of magnitude lower than previously demonstrated for hydrides under pressure. In this paper, we investigate within DFT+U the electronic structure of both parent lutetium hydride LuH${}_3$ and nitrogen doped lutetium hydride LuH${}_{2.75}$N${}_{0.25}$. We calculated corresponding bands, density of states and Fermi surfaces. It is shown that in the stoichiometric system the Lu-5d states cross the Fermi level while the H-1s states make almost no contribution at the Fermi level. However, with nitrogen doping, the N-2p states enter the Fermi level in large quantities and bring together a significant contribution from the H-1s states. The presence of N-2p and H-1s states at the Fermi level in a doped compound can facilitate the emergence of superconductivity. For instance, nitrogen doping almost doubles the value of DOS at the Fermi level. Simple BCS analysis shows that the nitrogen doping of LuH${}_3$ can provide T${}_c$ more than 100K and even increase it with further hole doping.

7 pages, 5 figures

References in corpus (18)

• Superconductivity at 253 K in lanthanum-yttrium ternary hydrides
• Superconducting hydrides under pressure
• Absence of near-ambient superconductivity in LuH${}_{2\pm \text{x}}$N${}_y$
• Search for ambient superconductivity in the Lu-N-H system
• High-temperature superconductivity in hydrides
• Pressure-induced color change in the lutetium dihydride LuH2
• First-principles study on the superconductivity of N-doped fcc-LuH3
• Lu-H-N phase diagram from first-principles calculations
• Structure, Stability and Superconductivity of N-doped Lutetium Hydrides at kbar Pressures
• Observation of non-superconducting phase changes in LuH${}_{2\pm \text{x}}$N${}_y$
• Effect of nitrogen doping and pressure on the stability of LuH${}_3$
• Pressure induced color change and evolution of metallic behavior in nitrogen-doped lutetium hydride
• On parent structures of near-ambient nitrogen-doped lutetium hydride superconductor
• Ab initio study of the structural, vibrational and optical properties of potential parent structures of nitrogen-doped lutetium hydride
• Pressure tuning of optical reflectivity in LuH2
• Electronic and magnetic properties of Lu and LuH${}_2$
• Enormous variation in homogeneity and other anomalous features of room temperature superconductor samples: a Comment on Nature 615, 244 (2023)
• Transformation of hexagonal Lu to cubic LuH${}_{2+x}$ single-crystalline films

Cited by in corpus (2)

• Novel Electronic Structure of Nitrogen-Doped Lutetium Hydrides
• Unveiling a Novel Metal-to-Metal Transition in LuH2: Critically Challenging Superconductivity Claims in Lutetium Hydrides