Temperature and Pressure Dependence of C-Axis Resistivity in Potassium-Hydrogen-Graphite Intercalation Compounds

Abstract

The c-axis resistivity ρ_c which indicates a metallic temperature dependence was measured in stage 1 and 2 potassium-hydrogen-graphite intercalation compounds (KH-GICs) in the temperature range of 1.5–300 K below 15 kbar. The pressure effect on ρ_c suggests a hopping conduction process for the c-axis transport mechanism, which is governed by the number of conduction paths and the transfer integral across the intercalate layer. The magnitudes of ρ_c in stage 1 and stage 2 compounds are mainly dominated by the number of their impurity and defects concentrations in the conduction paths.