Non-destructive broadband material characterization over the K-band using whispering-gallery-mode resonators

A precise technique for broadband material characterization, using a whispering-gallery-mode (WGM) resonator, is proposed. The resonant perturbation method is successfully applied for extracting both the dielectric constant and loss tangent of materials over a wide frequency band. Two experimental prototypes are fabricated and employed over the K-band where consistent results are obtained with a maximum error of ±3.3%.