Spin Splitting of Single 0D Impurity States in Semiconductor Heterostructure Quantum Wells

Zeeman splitting of the ground state of single impurities in the quantum well of a resonant tunneling heterostructure is reported. We determine the absolute magnitude of the effective magnetic spin splitting factor $g_{\perp }^{*}$ for a single impurity in a $44Å$ ${\mathrm{Al}}_{0.27}{\mathrm{Ga}}_{0.73}\mathrm{As}/\mathrm{GaAs}/{\mathrm{Al}}_{0.27}{\mathrm{Ga}}_{0.73}\mathrm{As}$ quantum well to be 0.28 $\pm$ 0.02. This system also allows for independent measurement of the electron tunneling rates through the two potential barriers and estimation of the occupation probability of the impurity state in the quantum well.