arXiv:2504.21144 · Physical Review Research
Electron beam characterization via quantum coherent electric field imaging
Rob Behary, Kevin Su, Nicolas DeStefano, Mykhailo Vorobiov, Todd D. Averett, A. Camsonne, Shukui Zhang, Charles Fancher, Neel Malvania, Eugeniy E. Mikhailov, S. Aubin, Irina V. Novikova
Abstract
We demonstrate an all-optical, minimally invasive electron beam ( e − beam ) characterization using Rydberg electrometry. An e -beam passes through a localized detector volume containing thermal Rb atoms that are optically excited in a quantum superposition of ground and Rydberg states. The e -beam's electric field perturbs atomic coherence and modifies resonance fluorescence in a narrow spectral region near the two-photon optical transition. Imaging Rb fluorescence provides a map of the electric field from the e -beam via Rydberg state Stark shifts and allows us to reconstruct the e -beam width, centroid position, and current. For an e -beam of 20 keV and electron currents of 20–40 µ A , we measured the centroid position with an accuracy of ≤ 8 µ m and width to within 100 µ m , limited by the experimental sensitivity of electric field reconstruction of ∼ 0.02 V/cm. This method is suitable for a wide range of electron energies and currents, and can be adopted for nuclear and high-energy experiments for minimally invasive real-time diagnostics and profiling of charged particle beams.