Coherence of Elementary Excitations in Disordered GaAs/AlGaAs Superlattices
نویسنده
چکیده
The localization properties of the single-particle and collective electron excitations were investigated in the intentionally disordered GaAs/AlGaAs superlattices by weak field magnetoresistance and Raman scattering. The localization length of the individual electron was found to be considerably larger than that one of the collective excitations. This suggests that the disorder has weaker effect on the electrons than on their collective motion and that the interaction which gives rise to the collective effects increases localization.
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