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arXiv · 0711.0517

Radiative Recombination Spectra of Heavily p-Type delta-Doped Gaas/Alas MQWs

J. Kundrotas·A. Cerskus·G. Valusis·M. Lachab·S. P. Khanna·P. Harrison·E. H. Linfield
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Abstract

We present a study of the photoluminescence (PL) properties of heavily Be delta-doped GaAs/AlAs multiple quantum wells measured at room and liquid nitrogen temperatures. Possible mechanisms for photocarriers recombination are discussed, with a particular focus on the peculiarities of the excitonic and free carriers-acceptors PL emissions occurring below and above the Mott metal-insulator transition. Moreover, based on a simple theoretical model, it is found that the critical impurities concentration to observe the Mott transition in the MQW samples exhibiting 15 nm wells width and 5 nm-thick barrier layers is about 3 10E12 cm-2.

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J. Kundrotas, A. Cerskus, G. Valusis, M. Lachab, S. P. Khanna, P. Harrison, E. H. Linfield. 2007-11-04. Radiative Recombination Spectra of Heavily p-Type delta-Doped Gaas/Alas MQWs. https://arxiv.org/abs/0711.0517

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