Effect of Sample Size on Measurement Reliability of Microwave Dielectric Properties of Low-Loss Materials by a Resonant Cavity Method

摘要

The microwave dielectric properties of SrTiO_3 and CaNdAlO_4 single crystals were measured by the resonant cavity method, and the effect of sample size on measurement reliability was investigated. High measurement accuracy could always be achieved for SrTiO_3, while the measurement was completely unreliable for CaNdAlO_4 with small sizes. The difference was attributed to the much higher dielectric constant and electric energy filling factor of SrTiO_3. It is indicated that the sample with much smaller size than usual might also be used for the resonant cavity method, as long as the electric energy filling factor of the sample was high enough.