Injection energy dependence of electron thermalization length in AlGaAs/GaAs quantum well structures

摘要

We have investigated the transport properties of hot electrons in AlGaAs/GaAs quantum well structures in real space by using a scanning tunneling microscope (STM). The electrons were injected from the STM tip at different distances from a target well. Then by measuring the light emission intensity from the target well, the thermalization and diffusion lengths of the injected electrons were determined. We found that the thermalization length increases with the increase of the initial energy of injection, while the diffusion length is independent of the injection energy.