Electron-phonon interaction in short-period (GaAs) m (AlAs) n (001) superlattices

Intervalley scattering of electrons by short-wave phonons in (GaAs)8(AlAs)8(001) superlattice

“…Our study identifies the deformation potentials for the actual electronic transitions in the conduction band of (GaAs) 8 (AlAs) 8 (001) superlattice. From the analysis of wave functions and pseudopotential gradients a ratio of the deformation potentials for different inter-valley scattering channels is explained.…”

“…The phonon spectrum n aq and phonons' polarization vectors e s i ðaqÞ in the superlattice were determined within the framework of a phenomenological model of interatomic forces and in the mass defect approximation [5,10]. The results of such calculations are in general agreement with ab-initio methods [8,11] but give more visual picture of the mechanisms of electron scattering by lattice vibrations.…”

“…The folding of a band spectra from binary crystals into the tetragonal Brillouin zone and a subsequent mixing of sphalerite states by the non-cubic potential component of (GaAs) 8 (AlAs) 8 (001) superlattice leads to a complex, multi-valley structure of its conduction band (Fig. 3a, Table 3).…”

“…It is shown that the deformation potentials for the majority of intervalley transitions in a superlattice exceed the potentials of corresponding transitions in the binary crystals because of the localization of atomic displacements and wavefunctions of electrons inside the same layer of the superlattice. The bottom of the conduction band in (GaAs) 8 (AlAs) 8 (001) superlattice corresponds to the states G …”

“…Intervalley transitions induced by short-wavelength phonons in the conduction band of a superlattice (GaAs) 8 (AlAs) 8 (001) are investigated on the basis of the pseudopotential method and in the phenomenological model of interatomic forces. The main attention in the study centers around the transitions associated with the vibrations confined inside the layers.…”