2011/03/11 by Claudio Verdozzi, Daniel Karlsson, Marc Puig von Friesen +4 · 29 citations
Physics and Astronomy · #Adiabatic process #Adiabatic theorem #Advanced Chemical Physics Studies #Cold Atom Physics and Bose-Einstein Condensates #Density functional theory #Lattice (music) #Physics #Quantum mechanics #Quantum, superfluid, helium dynamics #Statistical physics #Time-dependent density functional theory #cond-mat.mes-hall
paper · pdf · doi:10.1016/j.chemphys.2011.04.035
published in Chemical Physics 391(1), 37-49 (Elsevier BV) · 15 pages, submitted to Chemical Physics
arxiv created 2011/03/11 · openalex publication_date 2011/05/10 · arxiv updated 2015/05/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Two aspects of TDDFT, the linear response approach and the adiabatic local density approximation, are examined from the perspective of lattice models. To this end, we review the DFT formulations on the lattice and give a concise presentation of the time-dependent Kadanoff-Baym equations, used to asses the limitations of the adiabatic approximation in TDDFT. We present results for the density response function of the 3D homogeneous Hubbard model, and point out a drawback of the linear response scheme based on the linearized Sham-Schlüter equation. We then suggest a prescription on how to amend it. Finally, we analyze the time evolution of the density in a small cubic cluster, and compare exact, adiabatic-TDDFT and Kadanoff-Baym-Equations densities. Our results show that non-perturbative (in the interaction) adiabatic potentials can perform quite well for slow perturbations but that, for faster external fields, memory effects, as already present in simple many-body approximations, are clearly required.