Novel Thermal Transport in Stable Binary Cd 5.7 Yb Quasicrystals

Quasicrystalline materials have been investigated for application as thermoelectric materials due to their inherently low thermal conductivity. With the discovery of a new stable, binary Cd5.7Yb quasicrystal, thermal and electrical transport measurements have been performed on these materials. It is found that the electronic contribution to the thermal conductivity calculated from the Wiedemann-Franz relationship is comparable to or greater than the total measured thermal conductivity, leaving the appearance of a “negligible lattice contribution.” In addition, no semblance of the lattice contribution appears in the temperature dependence of the thermal conductivity. The thermal conductivity increases linearly with temperature above 75K and proportional to T3/4 between 2 K and 75 K.