Interacting-bath dynamical embedding for capturing non-local electron correlation in solids

Quantitative simulation of electronic structure of solids requires treating local and non-local electron correlations on an equal footing. We present a new ab initio formulation of Green's function embedding which, unlike dynamical mean-field theory that uses non-interacting bath, derives bath representation with general two-particle interactions in a systematically improvable manner. The resulting interacting-bath dynamical embedding theory (ibDET) utilizes an efficient real-axis coupled-cluster solver to compute the self-energy, approaching the full system limit at much reduced cost. When combined with the GW theory, GW+ibDET achieves good agreement with experimental spectral properties across a range of semiconducting, insulating and metallic materials. Our approach also enables quantifying the role of non-local electron correlation in determining material properties and addressing the long-standing debate on the bandwidth narrowing of metallic sodium.