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arXiv · 1402.3081

Screening of the quantum-confined Stark effect in AlN/GaN nanowire superlattices by Germanium doping

P. Hille·J. Müßener·P. Becker·M. de la Mata·N. Rosemann·C. Magén·J. Arbiol·J. Teubert·S. Chatterjee·J. Schörmann·M. Eickhoff
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Abstract

We report on electrostatic screening of polarization-induced internal electric fields in AlN/GaN nanowire heterostructures with Germanium-doped GaN nanodiscs embedded between AlN barriers. The incorporation of Germanium at concentrations above $10^{20}\,\text{cm}^{-3}$ shifts the photoluminescence emission energy of GaN nanodiscs to higher energies accompanied by a decrease of the photoluminescence decay time. At the same time, the thickness-dependent shift in emission energy is significantly reduced. In spite of the high donor concentration a degradation of the photoluminescence properties is not observed.

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P. Hille, J. Müßener, P. Becker, M. de la Mata, N. Rosemann, C. Magén, J. Arbiol, J. Teubert, S. Chatterjee, J. Schörmann, M. Eickhoff. 2014-02-13. Screening of the quantum-confined Stark effect in AlN/GaN nanowire superlattices by Germanium doping. https://doi.org/10.1063/1.4868411

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