Isotope effect in the thermal conductivity of germanium single crystals

Abstract

The thermal conductivity of chemically, structurally, and isotopically highly pure germanium single crystals is investigated experimentally in the temperature range from 2 to 300 K. It is found that the thermal conductivity of germanium enriched to 99.99% 70Ge is 8 times higher at the maximum than the thermal conductivity of germanium with the natural isotopic composition.