Electric field measurement with Electro-Optic sensor of high power W-band gyrotron

We present electric field measurement with Electro-Optic (EO) sensor of high power W-band gyrotron. EO sensors serve as minimally invasive field receivers as compared to metal-based electronic field probes. A rectangular waveguide WR-10 for W-band is used in order to calibrate the probe since the field strength inside the waveguide can be accurately calculated based on the output power measured by RF power meter. Then, the performance of the sensor is evaluated by high power W-band gyrotron and its measurement result of power is compared with that of calorimeter.