Anisotropic Conductivity in a Decagonal Quasicrystal of Al70Ni15Co15

Electrical resistivities have been measured from 4.2 K to 300 K for single-grained decagonal quasicrystals of Al 70 Ni 15 Co 15 . The conductivity is quite anisotropic; the resistivity along the c -axis (crystalline direction) is 50 µΩcm at 4.2 K and has a positive temperature coefficient, whereas that along a direction perpendicular to the c -axis (quasicrystalline direction) is as high as ∼1200 µΩcm at 4.2 K and also has a positive temperature coefficient in spite of the high resistivity.