Single-atom electron paramagnetic resonance in a scanning tunneling microscope driven by a radio-frequency antenna at 4 K

Open access
Author
Show all
Date
2020Type
- Journal Article
Citations
Cited 17 times in
Web of Science
Cited 21 times in
Scopus
ETH Bibliography
yes
Altmetrics
Abstract
Combining electron paramagnetic resonance (EPR) with scanning tunneling microscopy (STM) enables detailed insight into the interactions and magnetic properties of single atoms on surfaces. A requirement for EPR-STM is the efficient coupling of microwave excitations to the tunnel junction. Here, we achieve a coupling efficiency of the order of unity by using a radio-frequency antenna placed parallel to the STM tip, which we interpret using a simple capacitive-coupling model. We further demonstrate the possibility to perform EPR-STM routinely above 4 K using amplitude as well as frequency modulation of the radio-frequency excitation. We directly compare different acquisition modes on hydrogenated Ti atoms and highlight the advantages of frequency and magnetic-field sweeps as well as amplitude and frequency modulation in order to maximize the EPR signal. The possibility to tune the microwave-excitation scheme and to perform EPR-STM at relatively high temperature and high power opens this technique to a broad range of experiments, ranging from pulsed EPR spectroscopy to coherent spin manipulation of single-atom ensembles. Show more
Permanent link
https://doi.org/10.3929/ethz-b-000456234Publication status
publishedExternal links
Journal / series
Physical Review ResearchVolume
Pages / Article No.
Publisher
American Physical SocietyOrganisational unit
03986 - Gambardella, Pietro / Gambardella, Pietro
Funding
163225 - Local detection of spin accumulation by scanning probe microscopy (SNF)
More
Show all metadata
Citations
Cited 17 times in
Web of Science
Cited 21 times in
Scopus
ETH Bibliography
yes
Altmetrics