材料期刊网

The ground-state and lowest excited-state binding energies of a hydrogenic impurity in GaAs parabolic quantum-well wires(QWWs) subjected to external electric and magnetic fields are investigated using the finite-difference method within the quasi-one-dimensional effective potential model. We define an effective radius rho(eff) of a cylindrical QWW, which can describe the strength of the lateral confinement. For the ground state, the position of the largest probability density of electron in x-y plane is locate data point, while for the lowest excited state, is located on a circularity whose radius is rho(eff). The point and circularity are pushed along the left half of the center axis of the quantum-well wire by the electric field directed along the right half. When an impurity is located at the point or within the circularity, the ground-state or lowest excited-state binding energies are the largest;when the impurity is a part from the point or circularity, the ground-state or lowest excited-state binding energies start to decrease.