When does a crystal conduct heat like a glass?
- 1 December 2000
- journal article
- research article
- Published by Taylor & Francis in Philosophical Magazine Letters
- Vol. 80 (12) , 807-812
- https://doi.org/10.1080/09500830010003830
Abstract
Semiconducting crystalline materials that are poor conductors of heat are important as thermoelectric materials and for technological applications involving thermal management. A combination of neutron scattering, lowtemperature ultrasonic attenuation and thermal conductivity measurements are reported on single crystals of the semiconductors Sr8Ga16Ge30 and Ba8Ga16Ge30. Taken together, these measurements suggest specific structural features that result in a crystal with the lowest possible thermal conductivity, namely that of a glass with the same chemical composition. Weakly bound atoms that 'rattle' within oversized atomic cages in a crystal result in a low thermal conductivity, but the present data show that both 'rattling' atoms and tunnelling states are necessary to produce a true glass-like thermal conductivity.Keywords
This publication has 0 references indexed in Scilit: