Surface Kondo Effect and Non-Trivial Metallic State of the Kondo Insulator YbB12

Abstract

A synergistic effect between strong electron correlation and spin-orbit interaction (SOI) has been theoretically predicted to result in a new topological state of quantum matter on Kondo insulators (KIs), so-called topological Kondo insulators (TKIs). One TKI candidate has been experimentally observed on the KI SmB6(001), and the origin of the surface states (SS) and the topological order of SmB6 has been actively discussed. Here, we show a metallic SS on the clean surface of another TKI candidate YbB12(001), using angle-resolved photoelectron spectroscopy. The SS showed temperature-dependent reconstruction corresponding with the Kondo effect observed for bulk states. Despite the low-temperature insulating bulk, the reconstructed SS with c-f hybridization was metallic, forming a closed Fermi contour surrounding $\bar{\Gamma }$ on the surface Brillouin zone and agreeing with the theoretically expected behavior for SS on TKIs. These results demonstrate the temperature-dependent holistic reconstruction of two-dimensional states localized on KIs surface driven by the Kondo effect.

15 pages, 4 figures

References in corpus (1)

• Samarium hexaboride: A trivial surface conductor

Cited by in corpus (26)

• Interacting topological insulators: a review
• Quantum Oscillations of Electrical Resistivity in an Insulator
• Exceptional band touching for strongly correlated systems in equilibrium
• Unconventional thermal metallic state of charge-neutral fermions in an insulator
• Laser-irradiated Kondo insulators : Controlling Kondo effect and topological phases
• Non-trivial surface states of samarium hexaboride at the (111) surface
• Magnetic states in a three-dimensional topological Kondo insulator
• Chemical and valence reconstruction at the surface of SmB6 revealed with resonant soft x-ray reflectometry
• Metallic surface states in a correlated d-electron topological Kondo insulator candidate FeSb2
• Topological surface conduction in Kondo insulator YbB${}_{12}$
• Topological Phase Transition in an Archetypal f-electron Correlated System: Ce
• Hall anomaly, Quantum Oscillations and Possible Lifshitz Transitions in Kondo Insulator YbB${}_{12}$: Evidence for Unconventional Charge Transport
• Effects of strong correlations on the nonlinear response in Weyl-Kondo semimetals
• Evidence of electronic phase separation in the strongly correlated semiconductor YbB12
• Charge neutral fermions and magnetic field driven instability in insulating YbIr${}_3$Si${}_7$
• Crystal field potential and short-range order effects in inelastic neutron scattering, magnetization and heat capacity of the cage-glass compound HoB12
• Correlated Topological Mixed-Valence Insulators in Moiré Hetero-Bilayers
• An STM perspective on hexaborides: Surface states of the Kondo insulator SmB${}_6$
• Altermagnetism, ARPES, symmetry, non-relativistic band splitting
• Topology of SmB6 revisited by means of topological quantum chemistry
• Topological surface states in the Kondo insulator YbB${}_{12}$ revealed via planar tunneling spectroscopy
• Robust hybridization gap in a Kondo Insulator YbB${}_{12}$ probed by femtosecond optical spectroscopy
• Lieb-Schultz-Mattis constraints for the insulating phases of the one-dimensional SU($N$) Kondo lattice model
• Search for magnetoacoustic quantum oscillations in the insulating phase of YbB${}_{12}$
• Gapped electron liquid state in the symmetric Anderson lattice, Kondo insulator state
• Anisotropic Surface State Band Splitting and Low Energy Flat Bands in 3d Correlated Topological Kondo Insulator Candidate FeSb${}_2$