RESONANT DONOR STATES IN QUANTUM WELL

A method of calculation of donor impurity states in a quantum well is developed. The used techniques have made it possible to find the binding energy both of ground and excited impurity states attached to each QW subband. The positions of the resonant states in 2D continuum are determined as poles of corresponding wave functions. As a result of such an approach the identification of resonant states in 2D continuum is avoided, introducing special criterions. The calculated dependences of binding energies versus impurity position are presented for various widths of Si / Si 1-x Ge x quantum wells.