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Fermi-Edge Singularities in AlxGa1-xAs Quantum Wells : Extrinsic Versus Many-Body Scattering Processes

T. Melin·F. Laruelle
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Abstract

A Fano resonance mechanism is evidenced to control the formation of optical Fermi-edge singularities in multi-subband systems such as remotely doped AlxGa1-xAs heterostructures. Using Fano parameters, we probe the physical nature of the interaction between Fermi-sea electrons and empty conduction subbands. We show that processes of extrinsic origin like alloy-disorder prevail easily at 2D over multiple diffusions from charged valence holes expected by many-body scenarios.

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T. Melin, F. Laruelle. 2000-06-29. Fermi-Edge Singularities in AlxGa1-xAs Quantum Wells : Extrinsic Versus Many-Body Scattering Processes. https://doi.org/10.1103/physrevlett.85.852

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