Hole-Doping Effect on Superconductivity in Compressed CeH${}_9$ at High Pressure

Abstract

The experimental realization of high-temperature superconductivity in compressed hydrides H${}_3$S and LaH${}_{10}$ at high pressures over 150 GPa has aroused great interest in reducing the stabilization pressure of superconducting hydrides. For cerium hydride CeH${}_9$ recently synthesized at 80$-$100 GPa, our first-principles calculations reveal that the strongly hybridized electronic states of Ce 4$f$ and H 1$s$ orbitals produce the topologically nontrivial Dirac nodal lines around the Fermi energy $E_F$, which are protected by crystalline symmetries. By hole doping, $E_F$ shifts down toward the topology-driven van Hove singularity to significantly increase the density of states, which in turn raises a superconducting transition temperature $T_c$ from 74 K up to 136 K at 100 GPa. The hole-doping concentration can be controlled by the incorporation of Ce${}^{3+}$ ions with varying their percentages, which can be well electronically miscible with Ce atoms in the CeH${}_9$ matrix because both Ce${}^{3+}$ and Ce behave similarly as cations. Therefore, the interplay of symmetry, band topology, and hole doping contributes to enhance $T_c$ in compressed CeH${}_9$. This mechanism to enhance $T_c$ can also be applicable to another superconducting rare earth hydride LaH${}_{10}$.

References in corpus (28)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Magic-angle graphene superlattices: a new platform for unconventional superconductivity
• Weyl and Dirac Semimetals in Three Dimensional Solids
• Relativistic separable dual-space Gaussian Pseudopotentials from H to Rn
• Wannier90: A Tool for Obtaining Maximally-Localised Wannier Functions
• Conventional superconductivity at 203 K at high pressures
• WannierTools: An open-source software package for novel topological materials
• Tuning superconductivity in twisted bilayer graphene
• Superconductivity at 250 K in lanthanum hydride under high pressures
• Superconductivity in Iron Compounds
• Evidence for superconductivity above 260 K in lanthanum superhydride at megabar pressures
• EPW: Electron-phonon coupling, transport and superconducting properties using maximally localized Wannier functions
• Synthesis of clathrate cerium superhydride CeH9 below 100 GPa with atomic hydrogen sublattice
• Superconductive "sodalite"-like clathrate calcium hydride at high pressures
• Topological nodal line semimetals with and without spin-orbital coupling
• Dirac Line Nodes in Inversion Symmetric Crystals
• Topological nodal line semimetals
• Antiferromagnetic order and spin dynamics in iron-based superconductors
• A Perspective on Conventional High-Temperature Superconductors at High Pressure: Methods and Materials
• Node-Surface and Node-Line Fermions From Nonsymmorphic Lattice Symmetries
• Strain-induced partially flat band, helical snake states, and interface superconductivity in topological crystalline insulators
• Magic of high order van Hove singularity
• Hydrogen "penta-graphene-like" structure stabilized by hafnium: a high-temperature conventional superconductor
• Origin of High-Temperature Superconductivity in Compressed LaH${}_{10}$
• Ferromagnetic Weyl Fermions in Two-Dimensional Layered Electride Gd${}_2$C
• Multiband Nature of the Room-Temperature Superconductivity in Compressed LaH${}_{10}$
• Stabilization mechanism of clathrate H cages in a room-temperature superconductor LaH${}_{10}$
• Pressure dependence of the superconducting transition temperature of compressed LaH${}_{10}$

Cited by in corpus (4)

• Full-bandwidth anisotropic Migdal-Eliashberg theory and its application to superhydrides
• Potential high-$T_c$ superconductivity in YCeH${}_x$ and LaCeH${}_x$ under pressure
• Electron-phonon coupling and superconductivity in an alkaline earth hydride CaH${}_6$ at high pressures
• Impact of electronic correlations on the superconductivity of high-pressure CeH${}_9$