Study Of The Binding Energy Of D~0 And D~- Centers In 3D Spherical Quantum Dot

We briefly introduced properties and applications of quantum dot (QD), as well as theory research methods, we introduced the product base of harmonic oscillator and deduced the Tami-Moshinsky transformation bracket of three-dimensional.We studied a negative donor center, a neutral donor in a spherical Gaussian potential quantum dot by using the matrix diagonalization of Hamiltonian within the effective-mass approximation. We calculated the energy E as functions of Gaussian potential size and depth. The same calculations performed with the parabolic approximation. The dependence of the ground state of the neutral donor and the negatively charged donor on the dot size and the potential depth is investigated.First we get the energies in Gaussian potential and parabolic potential are similar. They decrease with the increase of the radius of the QD and the confinement strength. However, the quantitative differences are also obvious, in the strong confinement case, i.e. when the radius of the QD is small, the energies in the Gaussian potential are obviously lower than those in the parabolic potential.Then we get the binding energy of D⁰. The energy also decreases with the increase of R, and when R is large they reach a consistent. With different V₀, the binding energies aredifferent The binding energies are higher as the V₀ becomes smaller. The energies of V₀=100Ry^*and V₀=50Ry^*are similar, but whenV₀=10Ry^*, it is different The binding energy, when V₀=10Ry^* , increases with the increase of R at the beginning, it takes on the maximum at about R=0.7α_B^* and then decreases with the increase of R.The last we calculation the binding energies of the D^- center in a spherical QD with different V₀. There is a critical radius R_c ,when Rc the binding energy is negative,that isthe D^- center is unstable, it will be decomposed into a neutral donor and a free electron.