Transport properties (electrical and thermal conductivity and thermopower) of the high-quality samples of ξ ' Al-Pd-Mn and ψ Al-Pd-Mn giant-unit-cell materials were studied. Their electrical resistivities show weak temperature dependences between room and liquid helium temperatures, the resistivity values are higher than for regular metals and lower than for aluminum-based quasicrystals. The thermoelectric power is negative with complex temperature dependence, indicating the complexity of the electronic band structure. Thermal conductivity data show that the electronic and lattice contributions are of comparable size. While the electronic contribution can be described by the Wiedemann-Franz law, the lattice contribution could be reproduced by a sum of long-wavelength phonons and hopping of localized vibrations terms. These results that are in many respects different from both regular periodic metals and alloys and quasicrystals indicate that the transport properties of the giant-unit-cell complex metallic alloy materials are affected by both the quasiperiodic short-range atomic order and the long-range periodic order.

Fizika