Woptic: optical conductivity with Wannier functions and adaptive k-mesh refinement

TL;DR

This paper introduces Woptic, an adaptive Brillouin zone integration algorithm for optical and transport properties in crystalline materials, incorporating Wannier functions, many-body effects, and adaptive k-mesh refinement.

Contribution

The paper presents a novel adaptive integration algorithm integrated into the woptic package, enabling efficient calculation of optical and transport properties with many-body effects.

Findings

Efficient computation of optical conductivity for fcc-Al.

Inclusion of many-body self-energy effects in SrVO3.

Demonstration of adaptive k-mesh refinement benefits.

Abstract

We present an algorithm for the adaptive tetrahedral integration over the Brillouin zone of crystalline materials, and apply it to compute the optical conductivity, dc conductivity, and thermopower. For these quantities, whose contributions are often localized in small portions of the Brillouin zone, adaptive integration is especially relevant. Our implementation, the woptic package, is tied into the wien2wannier framework and allows including a many-body self energy, e.g. from dynamical mean-field theory (DMFT). Wannier functions and dipole matrix elements are computed with the DFT package Wien2k and Wannier90. For illustration, we show DFT results for fcc-Al and DMFT results for the correlated metal SrVO$_3$.