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The onset of exciton absorption in modulation doped GaAs quantum wells

G. Yusa·H. Shtrikman·I. Bar-Joseph
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Abstract

We study the evolution of the absorption spectrum of a modulation doped GaAs/AlGaAs semiconductor quantum well with decreasing the carrier density. We find that there is a critical density which marks the transition from a Fermi edge singularity to a hydrogen-like behavior. At this density both the lineshape and the transitions energies of the excitons change. We study the density dependence of the singularity exponent $α$ and show that disorder plays an important role in determining the energy scale over which it grows.

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G. Yusa, H. Shtrikman, I. Bar-Joseph. 2000-03-31. The onset of exciton absorption in modulation doped GaAs quantum wells. https://doi.org/10.1103/physrevb.62.15390

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