Non-Drude behaviour of optical conductivity in Kondo-lattice systems

Abstract

The optical conductivity in a Kondo lattice system is presented in terms of the memory function formalism. I use Kondo-lattice Hamiltonian for explicit calculations. I compute the frequency dependent imaginary part of the memory function (M (ω)), and the real part of the memory function M (ω) by using the Kramers-Kronig transformation. Optical conductivity is computed using the generalized Drude formula. I find that high frequency tail of the optical conductivity scales as σ(ω) ∼ 1 ω instead of the Drude 1 ω 2 law. Such a behaviour is seen in strange metals. My work points out that it may be the magnetic scattering mechanisms that are important for the anomalous behaviour of strange metals.