VOLUME LOW-FREQUENCY DISPERSION (LFD) IN HIGH-RESISTIVITY EPSILON-GASE

Dielectric measurements on high resistivity p-type epsilon-GaSe single crystals both parallel and perpendicular to the c-axis within Ag contacts were made in the frequency range 10(-3)-10(4) Hz and the temperature range 300-500 K. The complex susceptibility shows evidence of volume LFD at higher frequencies, with even more dispersive LFD at low frequencies and low temperatures, which eventually goes over into negative capacitance at higher temperatures, suggesting a parallel volume process. The dielectric data are isotropic. while different activation energies are seen in the parallel and perpendicular directions.