Imaging charged particle beams with atomic magnetometers

We develop a non-invasive approach to image charged particle current density and obtain its profile in 2 (and eventually 3) dimensions by analyzing the electron beam effect on the quantum state of surrounding alkali vapor. Specifically, we can measure the magnetic field of the moving electrons through nonlinear magneto-optical polarization rotation produced by the Rb atoms. By imaging the components of the optical field's polarization via cameras, we successfully detected characteristic signatures of the electron beam and extracted basic electron beam characteristics, such as its position, width, and current density. Potentially, such approach can produce a three-dimensional image of the beam by illuminating the interaction region from two orthogonal directions. While the immediate motivation for the project is its implementation as a high energy particle beam diagnostic tool for use at the Thomas Jefferson National Accelerator Facility, this approach to charged particle detection may have broad range of applications in nuclear and accelerator physics.