Plane-wave based electronic structure calculations for correlated materials using dynamical mean-field theory and projected local orbitals

Abstract

The description of realistic strongly correlated systems has recently advanced through the combination of density functional theory in the local density approximation (LDA) and dynamical mean field theory (DMFT). This LDA+DMFT method is able to treat both strongly correlated insulators and metals. Several interfaces between LDA and DMFT have been used, such as (N-th order) Linear Muffin Tin Orbitals or Maximally localized Wannier Functions. Such schemes are however either complex in use or additional simplifications are often performed (i.e., the atomic sphere approximation). We present an alternative implementation of LDA+DMFT, which keeps the precision of the Wannier implementation, but which is lighter. It relies on the projection of localized orbitals onto a restricted set of Kohn-Sham states to define the correlated subspace. The method is implemented within the Projector Augmented Wave (PAW) and within the Mixed Basis Pseudopotential (MBPP) frameworks. This opens the way to electronic structure calculations within LDA+DMFT for more complex structures with the precision of an all-electron method. We present an application to two correlated systems, namely SrVO3 and β-NiS (a charge-transfer material), including ligand states in the basis-set. The results are compared to calculations done with Maximally Localized Wannier functions, and the physical features appearing in the orbitally resolved spectral functions are discussed.

Fermi-surface evolution in Yb-substituted CeCoIn5

“…43 More sophisticated approaches, such as DFT + DMFT (dynamical mean field theory), could also improve our results. 44 It remains to be seen if such methods could improve the agreement of the effective masses for CeCoIn 5 , but this falls outside of the scope of the present study.…”

Computation of correlation-induced atomic displacements and structural transformations in paramagneticKCuF3andLaMnO3

“…Thereby multipole contributions to the electrostatic energy due to the distorted charge density distribution around the atom are ignored. Instead, the recently proposed implementation of the LDA+DMFT approach, which employs plane-wave pseudopotentials 25,26,27,28,29 and thus avoids the atomic sphere approximation, does not neglect such contributions. Thereby it becomes possible to describe the effect of the distortion on the electrostatic energy.…”

Phase Diagram and Electronic Structure of Praseodymium and Plutonium

“…[7][8][9][10][11]. LDA þ DMFT has been implemented in different basis sets, such as the linearized augmented plane wave (LAPW) [12,13], plane-wave pseudopotentials [14], the projector-augmented wave method [15], and linearized muffin-tin orbitals [16]. Another important approachwhich is not as accurate as DMFT but has the advantage to be less computationally demanding-is the Gutzwiller approximation (GA) [17][18][19], which was first implemented to study real solids in Ref.…”