Compartmentalization and optical conductivity in AlCuFe

Abstract

The frequency and temperature dependence of the optical conductivity of AlCuFe in quasicrystalline and rhombohedral phases is linear from ∼ 0.03eV up to energies E c  h ̵ ω max ∼ 1 eV . A microscopic compartmentalization model explains how this happens in AlCuFe and predicts E c in other quasicrystals. The model explains the various signs of the Hall voltages in the crystalline, quasicrystalline and amorphous phases of AlCuFe. It also explains both the successes and the failures of the pair hopping model for the linear conductivity of weakly compensated semiconductor impurity bands.