Optical absorption coefficient in quantum dot with Kratzer potential

Abstract In this work, we present a theoretical study of the optical absorption coefficient (OAC) in GaAs/AlGaAs spherical quantum dots (QDs) described by the Kratzer potential. By solving the Schrödinger equation, the quantized energy levels and wave functions of charge carriers are obtained, and an analytical expression for the OAC is derived using Fermi’s golden rule. Numerical calculations reveal discrete absorption peaks whose energies and intensities depend strongly on the quantum states involved, the dot radius, the confinement potential depth, and the temperature. Increasing the dot size leads to a red shift and enhanced absorption, while deeper confinement potentials induce a blue shift and stronger peaks. Temperature mainly reduces the absorption intensity through thermal broadening but leaves the spectral positions unchanged. These results highlight the roles of quantum confinement, dipole selection rules, and carrier distribution in shaping the optical response of semiconductor QDs and provide useful guidelines for tailoring the absorption properties of GaAs/AlGaAs nanostructures for optoelectronic and photonic applications.