Magnetic Manifestations of Carrier Confinement in Quantum Wells

A combination of superconducting integrated circuits was used to construct a very sensitive magnetooptic microsusceptometer for observations of the optically induced magnetization in ${\mathrm{Cd}}_{1-x}{\mathrm{Mn}}_x\mathrm{Te}$ multiple quantum wells. Spin-polarized electrons and holes are created optically, and the quantum mechanically localized wave functions of the carriers then serve as microscopic probes of the magnetic behavior. Both the magnitude and the picosecond dynamics of the magnetic response have been studied and reveal the effects of carrier quantization.