Evolution of multi-gap superconductivity in the atomically thin limit: Strain-enhanced three-gap superconductivity in monolayer MgB${}_2$

Abstract

Starting from first principles, we show the formation and evolution of superconducting gaps in MgB${}_2$ at its ultrathin limit. Atomically thin MgB${}_2$ is distinctly different from bulk MgB${}_2$ in that surface states become comparable in electronic density to the bulk-like $\sigma$- and $\pi$-bands. Combining the ab initio electron-phonon coupling with the anisotropic Eliashberg equations, we show that monolayer MgB${}_2$ develops three distinct superconducting gaps, on completely separate parts of the Fermi surface due to the emergent surface contribution. These gaps hybridize nontrivially with every extra monolayer added to the film, owing to the opening of additional coupling channels. Furthermore, we reveal that the three-gap superconductivity in monolayer MgB${}_2$ is robust over the entire temperature range that stretches up to a considerably high critical temperature of 20 K. The latter can be boosted to $>$50 K under biaxial tensile strain of $\sim$ 4\%, which is an enhancement stronger than in any other graphene-related superconductor known to date.

To appear in Phys. Rev

References in corpus (25)

• Optimized norm-conserving Vanderbilt pseudopotentials
• Evidence of Ising pairing in superconducting NbSe${}_2$ atomic layers
• Superconductivity in single-layer films of FeSe with a transition temperature above 100 K
• Characterization of collective ground states in single-layer NbSe2
• Superconductivity in the Intercalated Graphite Compounds C6Yb and C6Ca
• Electron-phonon interactions and related physical properties of metals from linear-response theory
• Quality heterostructures from two dimensional crystals unstable in air by their assembly in inert atmosphere
• Anisotropic Migdal-Eliashberg theory using Wannier functions
• Vortices with fractional flux in two-gap superconductors and in extended Faddeev model
• Evidence for superconductivity in Li-decorated monolayer graphene
• On-Chip Detection of Entangled Photons by Scalable Integration of Single-Photon Detectors
• Three-band superconductivity and the order parameter that breaks time-reversal symmetry
• A reliable Pade analytical continuation method based on a high accuracy symbolic computation algorithm
• Superconductivity in Ca-doped graphene
• Microscopic derivation of two-component Ginzburg-Landau model and conditions of its applicability in two-band systems
• Topological solitons in three-band superconductors with broken time reversal symmetry
• Two-dimensional Superconductors with Atomic-scale Thicknesses
• Two-band superconductors: Hidden criticality deep in the superconducting state
• Ginzburg-Landau theory for multiband superconductors: microscopic derivation
• Emergent phenomena in multicomponent superconductivity: an introduction to the focus issue
• Strain Enhanced Superconductivity in Li-Doped Graphene
• Electronic, dynamical and superconducting properties of CaBeSi
• Giant paramagnetic Meissner effect in multiband superconductors
• Anisotropic type-I superconductivity and anomalous superfluid density in OsB 2
• Critical temperature of MgB${}_2$ ultrathin superconducting films: BCS model calculations in tight-binding approximation

Cited by in corpus (28)

• Hydrogen-induced high-temperature superconductivity in two-dimensional materials: Example of hydrogenated monolayer MgB${}_2$
• Topological superconducting phase in high-Tc superconductor MgB2 with Dirac-nodal-line fermions
• High-Throughput DFT-Based Discovery of Next Generation Two-Dimensional (2D) Superconductors
• The Role of Odd-Frequency Pairing in Multiband Superconductors
• Phonon-mediated superconductivity in two-dimensional hydrogenated phosphorus carbide: HPC${}_3$
• Recent progress in the JARVIS infrastructure for next-generation data-driven materials design
• Full-bandwidth anisotropic Migdal-Eliashberg theory and its application to superhydrides
• Advanced first-principles theory of superconductivity including both lattice vibrations and spin fluctuations: The case of FeB${}_4$
• Superconductivity in monolayer Ba${}_2$N electride: a first-principles study
• Gap Anisotropy in Multiband Superconductors Based on Multiple Scattering Theory
• Superconductivity in functionalized niobium-carbide MXenes
• First-principles prediction of superconductivity in MgB${}_3$C${}_3$
• Phase solitons in a weakly coupled three-component superconductor
• Influence of electron-phonon coupling strength on signatures of even and odd-frequency superconductivity
• Strong electron-phonon coupling and predicted highest known $T_c$ of MXenes revealed in 2H-Mo${}_2$N under biaxial stress
• Two-dimensional non-van der Waals niobium nitride nanosheets with high-temperature two-gap superconductivity
• Electron-phonon coupling and superconductivity in LiB${}_{1+x}$C${}_{1-x}$
• Ab initio investigation on structural stability and phonon-mediated superconductivity in 2D-hydrogenated M2X (M= Mo, V, Zr; X=C, N) MXene monolayer
• Robust Ferrimagnetic Ground State and Suppressed Superconductivity in Two-Dimensional HC6
• Single layer clathrane: A potential superconducting two-dimensional (2D) hydrogenated metal borocarbide
• Stability, electronic disruption, and anisotropic superconductivity of hydrogenated trilayer metal tetraborides (MB${}_4$H; M=Be, Mg, Ca, Al)
• Periodicity of superconducting shape resonances in thin films
• Computer Simulation of Electronic Device for Generation of Electric Oscillations by Negative Differential Conductivity of Supercooled Nanostructured Superconductors in Electric Field
• Towards an effective mass model for the quasi-1D magnesium diboride superconducting nanostructures
• Superconductivity and topological behavior in gallenene
• Ginzburg-Landau surface energy of multiband superconductors: Derivation and application to selected systems
• Properties and challenges of hot-phonon physics in metals: MgB${}_2$ and other compounds
• Strain-triggered high-temperature superconducting transition in two-dimensional carbon allotrope