Magneto-Optical Measurement of High Magnetic Fields for Pulsed Power Accelerators

Electrical currents and magnetic fields generated in high energy pulsed power accelerators are key operation parameters. However, to date, accurate and precise magnetic field and electrical current measurements on these high energy pulsed power accelerators have proven to be very difficult. This difficulty in performing the measurement is partly due to the fact that traditional metallic-probe field sensors require electrical impedance matching and are prone to noise that interferes with the desired signal. A non-metallic based method for sensing magnetic fields is accomplished by utilizing the Faraday effect. We report on a magneto-optical based approach based on the Faraday effect that uses a rare earth element crystal to measure magnetic fields and requires no interfering metallic probes or components to disturb the measured field. Here we focus on device theory, operating parameters and a benchtop laboratory experiment that illustrates the principles of operation on a high energy pulsed power accelerator.