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Calculation of near-field scanning optical images of exciton, charged excition and multiexciton wavefunctions in self-assembled InAs/GaAs quantum dots

Lixin He·Gabriel Bester·Zhiqiang Su·Alex Zunger
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Abstract

The near-field scanning optical microscopy images of excitonic wavefunctions in self-assembled InAs/GaAs quantum dots are calculated using an empirical pseudopotential method, followed by the configuration interaction (CI) treatment of many-particle effects. We show the wavefunctions of neutral exciton $X^0$ of different polarizations, and compare them to those of the biexciton $XX$ and the charged excitons $X^+$ and $X^-$. We further show that the exciton $X(P_h \to S_e)$ transition which is forbidden in the far-field photoluminescence has comparable intensities to that of $X(S_h \to S_e)$ transition in the near-field photoluminescence .

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Lixin He, Gabriel Bester, Zhiqiang Su, Alex Zunger. 2007-03-26. Calculation of near-field scanning optical images of exciton, charged excition and multiexciton wavefunctions in self-assembled InAs/GaAs quantum dots. https://arxiv.org/abs/cond-mat/0703679

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