Electron-magnon coupling and quasiparticle lifetimes on the surface of a topological insulator

Abstract

The fermionic self-energy on the surface of a topological insulator proximity coupled to ferro- and antiferromagnetic insulators is studied. An enhanced electron-magnon coupling is achieved by allowing the electrons on the surface of the topological insulator to have a different exchange coupling to the two sublattices of the antiferromagnet. Such a system is therefore seen as superior to a ferromagnetic interface for the realization of magnon-mediated superconductivity. The increased electron-magnon-coupling simultaneously increases the self-energy effects. In this paper we show how the inverse quasiparticle lifetime and energy renormalization on the surface of the topological insulator can be kept low close to the Fermi level by using a magnetic insulator with a sufficient easy-axis anisotropy. We find that the antiferromagnetic case is most interesting from both a theoretical and an experimental standpoint due to the increased electron-magnon coupling, combined with a reduced need for easy-axis anisotropy compared to the ferromagnetic case. We also consider a set of material and instrumental parameters where these self-energies should be measurable in angle-resolved photoemission spectroscopy experiments, paving the way for a measurement of the interfacial exchange coupling strength.

14 pages, 9 figures, accepted in Physical Review B

References in corpus (13)

• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• Dirac materials
• Velocity Renormalization and Carrier Lifetime in Graphene from Electron-Phonon Interaction
• Electron-phonon coupling and electron self-energy in electron-doped graphene: calculation of angular resolved photoemission spectra
• Overdoping graphene beyond the van Hove singularity
• Non-sinusoidal current-phase relationship in Josephson junctions from the 3D topological insulator HgTe
• Phonon-induced many-body renormalization of graphene electronic properties
• Electron-phonon scattering in topological insulators
• Eliashberg study of superconductivity induced by interfacial coupling to antiferromagnets
• Strong electron-phonon coupling in the sigma band of graphene
• Magnon-mediated superconductivity on the surface of a topological insulator
• Possible odd-frequency Amperean magnon-mediated superconductivity in topological insulator -- ferromagnetic insulator bilayer
• Schwinger boson study of superconductivity mediated by antiferromagnetic spin-fluctuations

Cited by in corpus (15)

• Topological Superconductivity Mediated by Skyrmionic Magnons
• Many-body effects on superconductivity mediated by double-magnon processes in altermagnets
• Stability of superconducting gap symmetries arising from antiferromagnetic magnons
• Exceeding the Chandrasekhar-Clogston limit in flat-band superconductors: A multiband strong-coupling approach
• Magnon-mediated topological superconductivity in a quantum wire
• Distinguishing Surface and Bulk Electromagnetism via Their Dynamics in an Intrinsic Magnetic Topological Insulator
• Strong-coupling approach to temperature dependence of competing orders of superconductivity: Possible time-reversal symmetry breaking and nontrivial topology
• Spin-dependent quasiparticle lifetimes in altermagnets
• Tunable magnon band topology and magnon orbital Nernst effect in noncollinear antiferromagnets
• Electric polarization induced by magnons and magnon Nernst effects
• Magnon-mediated superconductivity on ferromagnetic wallpaper fermions
• Disentangling Electron-Boson Interactions on the Surface of a Familiar Ferromagnet
• Fate of surface gaps in magnetic topological insulators
• Topological phases of electrons induced by electron-magnon interactions
• Exchange tensors, generalized RKKY interactions, and magnetization dynamics in heterostructures of ferromagnets and topological insulators