Investigation of Single Atom Magnets using Scanning Tunneling Microscopy enabled Electron Spin Resonance


The smallest classical storage unit is a single atom bit. Its recent discovery in form of magnetically bistable holmium single atom magnets on MgO exemplified how miniaturization could be realized down to fundamental limits1 . Here we discuss the experiments leading to the observation of magnetic remanence1 , the reading and writing of single atom magnets 2 , and the investigation of their thermal and magnetic stability3 . Using STM enabled electron spin resonance4,5 , we find a magnetic moment of (10.1±0.1) Bohr magnetons and we prove the magnetic origin of the tunneling bias voltage dependent 2-state switching observed with spin-polarized current. We briefly review the used measurement concept of ESR-STM and illustrate new avenues for this technique.


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2. Natterer, F. D. et al. Reading and writing single-atom magnets. Nature 543, 226–228 (2017).

3. Natterer, F. D., Donati, F., Patthey, F. & Brune, H. Thermal and Magnetic-Field Stability of

Holmium Single-Atom Magnets. Phys. Rev. Lett. 121, 027201 (2018).

4. Baumann, S. et al. Electron paramagnetic resonance of individual atoms on a surface. Science 350,417–420 (2015).

5. Natterer, F. D. et al. Upgrade of a low-temperature scanning tunneling microscope for electron- spin resonance. ArXiv181003887 Cond-Mat Physics (2018).