Interband optical absorption in wurtzite GaN/InxGa1−xN/GaN spherical quantum dots with built-in electric field

Abstract

Based on the principle of density matrix and the finite element method, the interband optical absorption between the electron and hole has been investigated in a wurtzite [Formula: see text] spherical core–shell quantum dot (CSQD) including a strong built-in electric field (BEF). We have studied the effects of the size and the ternary mixed crystal on the optical absorption coefficients (ACs) and refraction index changes (RICs). The results indicate that the absorption peaks of ACs and RICs decrease rapidly, and show a redshift with the increase of the component [Formula: see text]. It is also found that the absorption peaks of ACs and RICs reduce obviously and depend on the core radius and the well width. When the core radius increases, the positions of the maximum ACs and RICs show a blueshift. At the same time, it presents a redshift when the well width increases. Particularly, the influence of the well width is much stronger than the core radius in the wurtzite [Formula: see text] spherical CSQDs. We hope that these results could provide guidance on both theoretical and experimental study related to the optical properties of spherical CSQDs.