Confinement effects on the low-field"high-field correspondences of hydrogenic impurity states in quasi-two-dimensional systems

Correspondences between low- and high-magnetic-field quantum-number assignments for hydrogenic impurity states in quasi-two-dimensional systems have been established. The apparent discrepancy between the assignments for three-dimensional and two-dimensional systems for excited states can be understood in terms of two different limiting cases. Far-infrared magneto-optical measurements have been carried out on well-center-doped Si donors in GaAs/Al0.3Ga0.7As multiple quantum wells with relatively narrow well width; the results show two-dimensional behavior, in agreement with the predictions in this well-width and magnetic-field region.