The dispersion law of holes bound at a screw dislocation in cubic semiconductors is calculated on the basis of deformation potential theory taking into account the threefold degeneracy of the valence band maximum in a perfect crystal. The lowest dislocation band (the corresponding azimuthal quantum number is rn = 0) is slightly affected by the anisotropy of the effective mass. Only the change of the effective mass is observed. The states with azimuthal number rn + 0 are considerably more affected by the anisotropy of the effective mass. A mixing of longitudinal and transverse motions (with respect to the dislocation line direction) takes place and terms linear in k,, appear in the dispersion law. The optical transitions associated with these states are intense for a polarization of light transverse with respect to the dislocation line and may cause circular dichroism in the absorption. The long-wave edge of the dislocation absorption on the whole is formed by transitions from the deepest band rn = 0 and is polarized along the Burgers vector 6.
B PaMKaX TeOpXEi
The bound electron states at an edge dislocation in direct gap semiconductors are investigated in the deformation potential model taking into account the triple degeneracy of the valence band maximum. The experimentally observed polarization of dislocation absorption (DA) and dislocation luminescence along the Burgers vector is explained theoretically. The interaction between the anisotropic dislocation field and the anisotropic valence subbands gives rise to three series of hole dislocation levels of different depths, the DA polarization being determined by the polarization of the optical transitions from the deepest holes series to the isotropic states of the conduction band.
The absorption profiles for different nanocomposite thin films are calculated in the frame of approach based on a local-field method for calculations of optical properties of nanocomposite thin films having a matrix topology. The electrodynamic interactions between the inclusions as well as inclusions-matrix interactions are explicitly taken into account. It is shown that the absorption spectra are strongly dependent both on inclusions concentration and on materials the nanocomposite is made of. The dependences of the effective dielectric functions of different nanocomposites on type of inclusions, and their volume fraction are analyzed. The optical properties of thin nanocomposite films with different distributions of identical spherical inclusions along the film thickness are studied.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.