title: Two-tier calibrated electro-optic sensing system for intense field characterization of high-power W-band gyrotron.
abstract: We present a field-calibrated electro-optic sensing system for measurement of the electric field radiating from a high-power vacuum oscillator at ~95 GHz. The intense electric field is measured in absolute scale via two probe-calibration steps, associated with a photonic heterodyne scheme. First, a micro-electro-optic probe, fabricated to less than one-tenth the oscillation wavelength scale to minimize field-perturbation due to the probe, is placed on the aperture of a field-calculable WR-10 waveguide to calibrate the probe in V/m scale. Then, using this arrangement as a calibrated reference probe at the first-tier position, another probe-bulkier, and thus more robust and sensitive but not accessible to the aperture-is calibrated at the second-tier position away from the waveguide aperture. This two-tier calibrated probe was utilized to diagnose the sub-MV/m scale of intense electric fields and emissions from a high-power W-band gyrotron. The experimental results obtained proved consistent with calculated analytical results-verifying the efficacy of the developed system.
authors.forename: Seok
authors.initials: S
authors.lastname: Kim
authors.forename: Young-Pyo
authors.initials: YP
authors.lastname: Hong
authors.forename: Jong-Won
authors.initials: JW
authors.lastname: Yang
authors.forename: Dong-Joon
authors.initials: DJ
authors.lastname: Lee