Vertical transport of hot electrons in GaAs/AlAs superlattices

Ballistic transport of hot photoexcited electrons injected from a superlattice into an enlarged quantum well is studied using the polarized hot photoluminescence technique. It is established that most photoexcited electrons thermalize before they are captured by the enlarged QW; however, a minor fraction of them reach the enlarged quantum well ballistically, keeping their momentum-distribution anisotropy or spin orientation arising due to the absorption of linearly or circularly polarized light in the superlattice.