Measurement of complex electrical conductivity of metallic powders in a sealed tube

We studied the method of complex-electrical-conductivity measurement for po wders placed in a sealed tube at microwave and millimeter-wave frequencies, using a cavity perturbation technique. We applied this technique to a mole cular superconductor K3C60, whose electrical conduction is well known in si ngle crystals, and reproduced the metallic conductivity with the magnitude of 0.5-1.2 m Omega cm at 20 K which is in good agreement with the data for single crystals. From this result, it was found that the cavity perturbatio n technique works well for the conductivity measurement of anaerobic powder s, with respect to metallic materials.