Condensed Matter Physics Seminar

First-principles study of strongly correlated systems:
Filling the missing pieces of the puzzles

Prof. Wei Ku
Physics Department, Brookhaven National Lab
Physics & Astronomy, SUNY Stony Brook
Tuesday, November 22, 2005
Higgins 235, 3pm

An overview of our novel attempts in realistic many-body problems from first-principles will be presented, covering the theoretical framework, recent tool development, several case studies, and future developments. Our recently developed multi-energy resolved Wannier functions play a central role in connecting the chemistry in the conventional density functional theory to local physics essential to strongly correlated systems. Intuitive microscopic picture will be presented concerning case studies of long-standing puzzles of gapless charge density wave in transition metal dichalcogenides, insulating ferromagnetism of half-filled La₄Ba₂Cu₂O₁₀, together with its isostructural antiferromagnetic counterpart, Nd₄Ba₂Cu₂O₁₀. Other case studies include origin of orbital ordering of manganites and system-dependent of low-lying states in high-T_c cuprates.