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arXiv · 1007.2733

Optical imaging of resonant electrical carrier injection into individual quantum dots

A. Baumgartner·E. Stock·A. Patanè·L. Eaves·M. Henini·D. Bimberg
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Abstract

We image the micro-electroluminescence (EL) spectra of self-assembled InAs quantum dots (QDs) embedded in the intrinsic region of a GaAs p-i-n diode and demonstrate optical detection of resonant carrier injection into a single QD. Resonant tunneling of electrons and holes into the QDs at bias voltages below the flat-band condition leads to sharp EL lines characteristic of individual QDs, accompanied by a spatial fragmentation of the surface EL emission into small and discrete light- emitting areas, each with its own spectral fingerprint and Stark shift. We explain this behavior in terms of Coulomb interaction effects and the selective excitation of a small number of QDs within the ensemble due to preferential resonant tunneling paths for carriers.

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A. Baumgartner, E. Stock, A. Patanè, L. Eaves, M. Henini, D. Bimberg. 2010-07-16. Optical imaging of resonant electrical carrier injection into individual quantum dots. https://doi.org/10.1103/physrevlett.105.257401

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