The Franck-Hertz experiment was the first to demonstrate the quantization of atomic energy levels using electrons, leveraging inelastic scattering. We want to demonstrate coherent interactions between electrons and two-level systems using the non-radiative near-field of a spatially deflected electron beam. I will discuss recent progress on the our setup, which consists of an adapted Philipps XL30 Scanning Electron Microscope. The electron beam is electrostatically deflected and passes by a spin ensemble to perform steady-state Electron Spin Resonance (ESR), which is read out inductively using a microcoil and a combination of heterodyne and lock-in detection. This could pave the way for coherent manipulation of quantum systems utilizing electrons, higher spatial resolution, non-destructive analytics by combining ESR and electron microscopy, using custom painted potentials from modulated electron beams
Kolb et al. (Wed,) studied this question.