Phason-Strain Influence on Low-Temperature Specific Heat ofthe Decagonal Al-Ni-Co Quasicrystal

According to the quasicrystal continuum model and linear elasticity theory, based on the equivalence assumption of phonons and phasons in quasicrystals we have deduced five phase-velocities of elastic wave propagating in the decagonal quasicrystals. By inserting these velocities into the specific heat expression, we have successed in explaining the experiment of specific heat performed on the single-grained decagonal Al-Ni-Co quasicrystals at low temperature. Our results show that the contribution of the phason-strain to the specific heat cannot be neglected at low-temperature. Moveover, the phason-strain may be a main reason that the decagonal quasicrystals possess anisotropic thermal conductivity.