SKM 2021 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MA: Fachverband Magnetismus

MA 1: Surface Magnetism (joint session MA/O)

MA 1.1: Hauptvortrag

Montag, 27. September 2021, 10:00–10:30, H5

Utilizing Vacuum States above Surfaces for Imaging and Manipulation of Atomic-Scale Magnetism — •Anika Schlenhoff — Department of Physics, University of Hamburg, Germany

Non-collinear spin textures in ultra-thin films raise expectations for spintronic applications, demanding for atomic-scale, spin-sensitive, but yet robust probe techniques. Spin-polarized vacuum resonance states (sp-RS) are unoccupied electronic states in the vacuum gap between a probe tip and a magnetic sample. They exhibit the same local spin quantization axis as the surface, even when it rotates on the atomic scale [1]. In a spin-polarized scanning tunneling microscopy (SP-STM) setup, the sp-RS can be addressed by spin-polarized electrons tunneling resonantly from the magnetic tip via these states into the surface. As I will show, this technique allows for atomic-scale magnetic imaging at tip-sample distances of up to 8 nm, providing a loophole from the hitherto existing dilemma of losing spatial resolution when increasing the tip-sample distance in a scanning probe setup [2]. Experimental results will be discussed in terms of the sp-RS’ spin-splitting and the magnetic contrast as a function of bias and tip-sample distance, and in terms of the atomic-scale nature of the resonant tunneling condition. In combination with thermally-assisted spin-transfer torque switching via sp-RS [3], our approach qualifies for a spin-sensitive read-write technique with ultimate lateral resolution in future spintronic applications. [1] A. Schlenhoff et al., Phys. Rev. Lett. 123, 087202 (2019). [2] A. Schlenhoff et al., Appl. Phys. Lett. 116, 122406 (2020). [3] A. Schlenhoff et al., Phys. Rev. Lett. 109, 097602 (2012).