An Alternative Mechanism of Heat Transport in Icosahedral $i$-AlPdMn Quasicrystals

Abstract

We propose a new theoretical approach to analyze the experimental data for thermal conductivity of single-grain $i$-AlPdMn quasicrystals. The interpretation is based on the picture where cluster interfaces are the main source of phonon scattering at low temperatures. The scattering due to strain fields of cluster interface is considered in terms of finite dislocation wall or, equivalently, wedge disclination dipole. Our numerical calculations show that experimentally observed thermal conductivity in a wide temperature range can be well fitted by a combination of wedge discliantion dipole scattering and quasiumklapp scattering processes.