The in-plane optical anisotropy for a common-atom superlattice in a uniform electric field is investigated numerically. A Hamiltonian that represents a common-atom (001)- grown superlattice system in a uniform electric field is set up from the eight-band k⋅p Hamiltonian for bulk crystal. A δ function interface potential that implies mixing between light and heavy holes is added in the Hamiltonian. Planewave expansion of a uniform electric field is derived to include the effect of the uniform electric field which is crucial in the existence of the in-plane optical anisotropy of a common-atom superlattice system. Reflectance difference spectra (RDS) of a GaAs/A1As superlattice in a uniform electric field with varying strength of interface potential and electric field are calculated to com...[ Read more ]

The in-plane optical anisotropy for a common-atom superlattice in a uniform electric field is investigated numerically. A Hamiltonian that represents a common-atom (001)- grown superlattice system in a uniform electric field is set up from the eight-band k⋅p Hamiltonian for bulk crystal. A δ function interface potential that implies mixing between light and heavy holes is added in the Hamiltonian. Planewave expansion of a uniform electric field is derived to include the effect of the uniform electric field which is crucial in the existence of the in-plane optical anisotropy of a common-atom superlattice system. Reflectance difference spectra (RDS) of a GaAs/A1As superlattice in a uniform electric field with varying strength of interface potential and electric field are calculated to compare with the experimental data. The line shape of the calculated RDS is found in qualitative agreement with experimental one. This calculation approach is easy to extend to include more bands such as fourteen bands and more mixing between different bands such as Γ -X or Γ -L mixing to obtain a more realistic and accurate result.