Recombination energy for excitonic trions in quantum dots

A theoretical study of excitonic trions, X- and X-2(+), in semiconductor qu antum dots is presented. The model of a spherical quantum well of finite de pth is applied to determine the influence of the three-dimensional quantum confinement on the recombination energies of the excitonic trions. A new ty pe of variational wave function, expanded in a Gaussian basis, has been pro posed. It is shown that the blue-shift of the recombination induced by the quantum confinement is much stronger for the positive trion X-2(+) than for the negative trion X-.