Hybridization of local Frenkel excitons in strongly interacting NiO

ORAL

Abstract

Recent experimentally observed tightly bound excitons in NiO are explained by a newly developed linear response theory within LDA+U approximation. A novel picture of local Frenkel excitons naturally emerges from a real space formulation of exciton formation using the energy- resolved Wannier functions. Systematic analysis of microscopic interacting processes reveals that the large 1 eV splitting between the excitons is due to a strong hybridization between the Frenkel excitons via strong local interactions. Our new picture can be viewed as a simplest representation of the charge excitation involving complex multiplet structure in strongly correlated systems.

*supported by DOE-BES DE-AC02-98CH10886, and in part by DOE-CMSN

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Authors

  • Wei Ku

    • Brookhaven National Laboratory
    • CMPMSD, Brookhaven National Lab; Physics Department, State University of New York, Stony Brook

  • Chi-Cheng Lee

    • CMPMSD, Brookhaven National Lab; Physics Department, Tamkang University, Taiwan, R.O.C.

  • Hung-Chung J. Hsueh

    • Physics Department, Tamkang University, Taiwan, R.O.C.