Coulomb correlated multiparticle states of weakly confining GaAs quantum dots

We compute the electronic and emission properties of Coulomb–correlated multiparticle states ( X 0 , X ± , XX ) in weakly confining GaAs/AlGaAs quantum dots using an eight-band k · p model coupled to continuum elasticity and configuration interaction (CI). We evaluate polarization-resolved oscillator strengths and radiative rates both in the dipole approximation and in a quasielectrostatic beyond-dipole (BDA) longitudinal formulation implemented via a Poisson reformulation exactly equivalent to the dyadic Green-tensor kernel. For the dots studied, BDA yields lifetimes in quantitative agreement with experiments, e.g., τ X = 0.279 ns vs 0.267 ns (exp.) and τ X X = 0.101 ns vs 0.115 ns (exp.). The framework also reproduces electric-field tuning of the multiparticle electronic structure and emission—including the indistinguishability inferred from P = τ X / ( τ X + τ X X ) —and we assess sensitivity to CI-basis size and to electron–electron and hole–hole exchange.