Magnetic excitations on 2H-NbSe2 - from adatoms and molecules to magnetically coupled nanostructures on a type II superconductor

• Applicant: Dr. Benjamin Heinrich
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2016 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 319541154

The transition metal dichalcogenide 2H-NbSe2 is a well-studied type II superconductor with anisotropic s-wave superconductivity, which is two-dimensional-like. Within this project, we will explore the local interaction of paramagnetic adatoms, molecules and artificial nanostructures with this particular type of superconductor by means of scanning tunneling microscopy and spectroscopy (STM/STS), which offers high energetic and spatial resolution. We will resolve magnetic ground and excited states to identify different coupling regimes with the substrate and the spatial extend of induced many-body states. By means of a perpendicular magnetic field, we will bring the substrate into the vortex state. This allows us to study similar magnetic impurities in gradually changing environments, from the vortex core with high B-fields, to regions of decreasing fields and increasing superconductivity, and superconducting regions with still persisting B-fields. Finally, we will investigate short- and long-range coupling mechanisms between impurities, which strongly rely on the anisotropic character of the superconductivity in 2H-NbSe2, and enable the construction of nanostructures with designed spin properties and topological phases.

• DFG Programme: Research Grants