Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5457219 | Solid State Communications | 2017 | 5 Pages |
Abstract
We study the combined effects of local and nonlocal hybridization on the formation and condensation of the excitonic bound states in the extended Falicov-Kimball model by the density-matrix-renormalization-group (DMRG) method. Analysing the resultant behaviours of the excitonic momentum distribution N(q) we found, that unlike the local hybridization V, which supports the formation of the q=0 momentum condensate, the nonlocal hybridization Vn supports the formation of the q=Ï momentum condensate. The combined effect of local and nonlocal hybridization further enhances the excitonic correlations in q=0 as well as q=Ï state, especially for V and Vn values from the charge-density-wave (CDW) region. Strong effects of local and nonlocal hybridization are observed also for other ground-state quantities of the model such as the f-electron density, or the density of unbound d-electrons, which are generally enhanced with increasing V and Vn. The same calculations performed for nonzero values of f-level energy Ef revealed that this model can yield a reasonable explanation for the pressure-induced resistivity anomaly observed experimentally in TmSe0.45Te0.55 compound.
Related Topics
Physical Sciences and Engineering
Materials Science
Materials Science (General)
Authors
Pavol Farkašovský,