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arXiv · 1107.0620

Influences of excitation-dependent bandstructure changes on InGaN light-emitting diode efficiency

Weng W. Chow
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Abstract

Bandstructure properties in wurtzite quantum wells can change appreciably with changing carrier density because of screening of quantum-confined Stark effect. An approach for incorporating these changes in an InGaN light-emitting-diode model is described. Bandstructure is computed for different carrier densities by solving Poisson and k\cdotp equations in the envelop approximation. The information is used as input in a dynamical model for populations in momentum-resolved electron and hole states. Application of the approach is illustrated by modeling device internal quantum efficiency as a function of excitation.

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Weng W. Chow. 2011-07-04. Influences of excitation-dependent bandstructure changes on InGaN light-emitting diode efficiency. https://doi.org/10.1364/oe.19.021818

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