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arXiv · 2412.02686

Electron Beam Characterization via Quantum Coherent Optical Magnetometry

Nicolas DeStefano·Saeed Pegahan·Aneesh Ramaswamy·Seth Aubin·T. Averett·Alexandre Camsonne·Svetlana Malinovskaya·Eugeniy E. Mikhailov·Gunn Park·Shukui Zhang·Irina Novikova
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Abstract

We present a quantum optics-based detection method for determining the position and current of an electron beam. As electrons pass through a dilute vapor of rubidium atoms, their magnetic field perturb the atomic spin's quantum state and causes polarization rotation of a laser resonant with an optical transition of the atoms. By measuring the polarization rotation angle across the laser beam, we recreate a 2D projection of the magnetic field and use it to determine the e-beam position, size and total current. We tested this method for an e-beam with currents ranging from 30 to 110 μA. Our approach is insensitive to electron kinetic energy, and we confirmed that experimentally between 10 to 20 keV. This technique offers a unique platform for non-invasive characterization of charged particle beams used in accelerators for particle and nuclear physics research.

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Nicolas DeStefano, Saeed Pegahan, Aneesh Ramaswamy, Seth Aubin, T. Averett, Alexandre Camsonne, Svetlana Malinovskaya, Eugeniy E. Mikhailov, Gunn Park, Shukui Zhang, Irina Novikova. 2024-12-03. Electron Beam Characterization via Quantum Coherent Optical Magnetometry. https://arxiv.org/abs/2412.02686

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