New analysis explains why some materials are good thermal
insulators while similar ones are not.
Materials that can be used for thermoelectric devices —
those that turn a temperature difference into an electric voltage — have been
known for decades. But until now there has been no good explanation for why
just a few materials work well for these applications, while most others do
not. Now researchers at MIT and elsewhere say they have finally found a theoretical
explanation for the differences, which could lead to the discovery of new,
improved thermoelectric materials.