Electrical conduction in nanocomposites of copper in silicate glasses

Abstract
Nanocomposites of metallic copper in a silica-based glass have been prepared by the hot compaction of ion-exchanged and reduced glass powders. The diameter of copper particles ranges from 5.7 to 9.2 nm. The specimens exhibit a semiconducting behaviour in the temperature range 80 - 333 K with an unusually low activation energy of the order of 3.0 meV. This result appears to be consistent with a quantum size effect.