2005/09/30 by H. Ouerdane, R. Varache, M. E. Portnoi +1
Chemistry · Physics and Astronomy · #Advanced Physical and Chemical Molecular Interactions #Biexciton #Elastic scattering #Exciton #Impact ionization #Ionization #Photon #Quantum and electron transport phenomena #Quantum well #Scattering #Semiconductor #Semiconductor Quantum Structures and Devices #cond-mat.other
paper · pdf · doi:10.1140/epjb/e2008-00355-x
published as The European Physical Journal B vol. 65, p.195 (2008) · Thoroughly revised version of previous work. Weak and incorrect assumptions have been removed from the paper, and its scope has evolved: see abstract. This is the final version, i.e. as accepted for publication in the European Physical Journal B
arxiv created 2008/08/07 · openalex publication_date 2008/09/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present a study of the elastic exciton--electron (X-e-) and exciton--hole (X-h) scattering processes in semiconductor quantum wells, including fermion exchange effects. The balance between the exciton and the free carrier populations within the electron-hole plasma is discussed in terms of ionization degree in the nondegenerate regime. Assuming a two-dimensional Coulomb potential statically screened by the free carrier gas, we apply the variable phase method to obtain the excitonic wavefunctions, which we use to calculate the 1s exciton--free carrier matrix elements that describe the scattering of excitons into the light cone where they can radiatively recombine. The photon emission rates due to the carrier-assisted exciton recombination in semiconductor quantum-wells (QWs) at room temperature and in a low density regime are obtained from Fermi's golden rule, and studied for mid-gap and wide-gap materials. The quantitative comparison of the direct and exchange terms of the scattering matrix elements shows that fermion exchange is the dominant mechanism of the exciton--carrier scattering process. This is confirmed by our analysis of the rates of photon emission induced by electron-assisted and hole-assisted exciton recombinations.