SEMIMETALLIC BEHAVIOR OF I-ALCUFE QUASI-CRYSTALS

We report on new measurements of the electrical conductivity, Hall eff ect and thermoelectric power in the temperature range from 2 K to 440 K for AlCuFe quasicrystals of different compositions and annealing tre atments. Particularly, the Hall coefficient and the thermopower show a strong dependence on composition and also on heat treatment. The incr ease of sample perfection on annealing between 810-degrees-C and 825-d egrees-C is demonstrated by analysing X-ray measurements. All measured quantities can be explained in terms of a semimetal containing both e lectrons and holes at low temperatures, at least for samples near the ideal quasicrystalline structure and composition.