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Publication # 066 |
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| D. A. B. Miller, D. S. Chemla and S.
Schmitt-Rink, "Relation Between Electroabsorption in Bulk Semiconductors and in
Quantum Wells: The Quantum-Confined Franz-Keldysh Effect," Phys. Rev. B33,
6976-6982 (1986). The authors evaluate the interband optical absorption of a semiconductor quantum well in the presence of a uniform electric field perpendicular to the layer and neglecting excitonic effects. They show that this formally becomes the Franz-Keldysh effect in the limit of an infinitely thick layer. When the potential drop across the layer is small compared to the confinement energy the authors obtain behavior qualitatively different from the bulk Franz-Keldysh effect and they explain this in terms of a quantum-confined Franz-Keldysh effect; with increasing field they demonstrate numerically for a GaAs-like semiconductor that they recover Franz-Keldysh-like behavior, once the originally 'forbidden' quantum-well transitions become strong. The authors' discussion gives an alternative physical picture for the Franz-Keldysh effect, including a simple explanation of the Franz-Keldysh oscillations |
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