title: Fermi-edge singularities in AlxGa1-xAs quantum wells: extrinsic versus many-body scattering processes
abstract: A Fano resonance mechanism is evidenced to control the formation of optical Fermi-edge singularities in multisubband 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.
authors.affiliation: Laboratoire de Microstructures et de Microelectronique, Centre National de la Recherche Scientifique, 196 Avenue Henri Ravera, BP 107, 92225 Bagneux Cedex, France.
authors.initials: T
authors.lastname: Melin
authors.initials: F
authors.lastname: Laruelle