  High-temperature thermal properties of three neighboring rare-earth scandates
DyScO$_3$, TbScO$_3$ and GdScO$_3$ were compared to
La$_{0.29}$Sr$_{0.71}$Al$_{0.65}$Ta$_{0.35}$O$_3$ (LSAT) and sapphire. To
calculate thermal conductivity, heat capacity and thermal diffusivity were
measured by differential scanning calorimetry and laser flash technique,
respectively. DyScO$_3$ and TbScO$_3$ showed an untypical rise in the thermal
conductivity above 900\,K, while for GdScO$_3$, LSAT and sapphire the expected
decrease at elevated temperatures could be observed. These results lead to the
proposal of a new type of heat transport by migrating ions.
