Modeling n$n$‐Type GaAs/AlGaAs Double Quantum Well Properties with Schrödinger‐Poisson Equations

Abstract

Delta‐doped double quantum wells (DQWs) have emerged as promising structures for advanced applications, such as high‐performance field‐effect transistors. This study examines GaAs, a material known for its direct bandgap and high electron mobility, employing the effective mass approximation to investigate the transport mobility and optical properties of ‐type doped GaAs/AlGaAs DQWs. This system is modeled by coupling the Schrödinger and Poisson equations, solving them with the finite element method. This findings indicate that structural adjustments can effectively tune the absorption coefficient, electron state occupancy, and electron mobility. As the quantum well (QW) width increases or the doping concentration decreases, the absorption coefficient shifts to lower energies, though it varies non‐monotonically with barrier and delta widths. Additionally, the impurity scattering rate, inversely related to electron transport mobility, decreases for the first five excited states as the barrier and well widths expand. These results offer valuable insights for optimizing optoelectronic device performance.