Excitonic effects in time-dependent density-functional theory: An analytically solvable model

  title={Excitonic effects in time-dependent density-functional theory: An analytically solvable model},
  author={R. Stubner and Ilya V. Tokatly and O. A. Pankratov},
  journal={Physical Review B},
Calculation of electronic excitation spectra remains one of the central problems of the quantum theory of solids. Of special interest are two-particle electron-hole excitations, which determine the material’s optical properties. In semiconductors and insulators the electronic screening is suppressed by the energy gap and the interaction of the excited quasiparticles may substantially modify the excitation spectrum. The excitonic effects stemming from this interaction comprise the formation of… 
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