Berlin 2024 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 52: Focus Session: Spins on Surfaces studied by Atomic Scale Spectroscopies V
O 52.3: Talk
Wednesday, March 20, 2024, 15:45–16:00, MA 004
Spin polarization of the Kondo system in mirror twin boundaries of MoS2 — •Mahasweta Bagchi1, Tfyeche Tounsi1, Affan Safeer1, Camiel van Efferen1, Thomas Michely1, Wouter Jolie1, Theo A. Costi2, and Jeison Fischer1 — 1II. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 Cologne, Germany — 2Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich, 52425 Jülich, Germany
We report spin-polarized scanning tunneling microscopy measurements of the Kondo effect observed in mirror twin boundaries of MoS2 on graphene, which are consistent with numerical renormalization group calculations. A Kondo resonance appears because the magnetic moment of a singly occupied quantum confined state of the mirror twin boundary is screened by the conduction electrons from the substrate [1]. Using a spin-polarized tip, we measure the Kondo resonance and the singly and doubly occupied confined levels simultaneously, characterizing the full Anderson system. Clear changes in the peak heights of the confined states as well as the magnetic field-split Kondo state provide evidence of their full spin polarization. The magnetization of the confined level as a function of magnetic field and temperature can be described as single quantum spin. This, along with the absence of any higher spin excitations, establishes the mirror twin boundary of MoS2 as an ideal spin 1/2 system.
[1] van Efferen, et al., Modulated Kondo screening along magnetic mirror twin boundaries in monolayer MoS2. Nat. Phys. (2023).
Keywords: spin-polarized scanning tunneling microscopy; transition-metal dichalcogenide; Kondo; mirror-twin boundary; magnetism