Weak localization in an anisotropic crystal: Decagonal quasicrystal Al₆₅Cu₁₅Co₂₀

Weak localization (WL) in three-dimensional anisotropic systems has been investigated by measuring the magnetoresistance (MR) of decagonal quasicrystal Al₆₅Cu₁₅Co₂₀. Both transverse and longitudinal MR measurements have been made for temperatures between 2 and 35 K in fields up to 5 T on single crystals with transport anisotropic ratio δ=D_z/D_qc∼8 at 300 K, where D_z and D_qc are diffusion constants along the periodical direction and the quasicrystal plane, respectively. The data can be well described by WL theory, with spin-orbit scattering time τ_so=1.75×10^-12 s and inelastic scattering time τ_ie=6.3×10^-10T^-1.7 s, which are comparable to those of i-phase quasicrystals such as AlCuFe and AlCuRu. Furthermore, the scaling between transverse and longitudinal MR provides verification of the WL theory for anisotropic systems proposed by Al'tshuler et al.