THEORETICAL CALCULATIONS OF SHALLOW DONOR IMPURITY STATES IN GAAS/GAALAS MULTIQUANTUM WELLS WITH MAGNETIC-FIELDS APPLIED PARALLEL TO THE LAYERS

A method is presented for the calculation of the energy eigenvalues and eigenstates of the electron associated with a shallow donor impurity in a GaAs/GaAlAs multi-quantum well structure in the presence of a magnetic field parallel to the layers. Compared to the case of an impurity in a magnetic field directed perpendicular to the layers, the problem is complicated by the lack of cylindrical symmetry. This lack of symmetry is reflected in the form chosen here for the basis states that describe the donor electron. By formulating the Hamiltonian and operating on these states, the energies and orthonormal ground and excited state wavefunctions of the donor electron are determined by matrix diagonalization procedures. Calculations of the transition probability between the ground and excited states yield the theoretically most probable transition energy for a given magnetic field. These calculated values are compared to available experimental data and deviations between the theory and experiments at large fields are discussed.