Rights statement: Copyright 2014 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Applied Physics Letters, 115 (1), 2014 and may be found at http://scitation.aip.org/content/aip/journal/jap/115/1/10.1063/1.4861129
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Photocapacitance study of type-II GaSb/GaAs quantum ring solar cells
AU - Wagener, Magnus C.
AU - Carrington, Peter James
AU - Botha, Johannes Reinhardt
AU - Krier, Anthony
N1 - Copyright 2014 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Applied Physics Letters, 115 (1), 2014 and may be found at http://scitation.aip.org/content/aip/journal/jap/115/1/10.1063/1.4861129
PY - 2014/1/7
Y1 - 2014/1/7
N2 - In this study, the density of states associated with the localization of holes in GaSb/GaAs quantum rings are determined by the energy selective charging of the quantum ring distribution. The authors show, using conventional photocapacitance measurements, that the excess charge accumulated within the type-II nanostructures increases with increasing excitation energies for photon energies above 0.9 eV. Optical excitation between the localized hole states and the conduction band is therefore not limited to the Γ(k = 0) point, with pseudo-monochromatic light charging all states lying within the photon energy selected. The energy distribution of the quantum ring states could consequently be accurately related from the excitation dependence of the integrated photocapacitance. The resulting band of localized hole states is shown to be well described by a narrow distribution centered 407 meV above the GaAs valence band maximum.
AB - In this study, the density of states associated with the localization of holes in GaSb/GaAs quantum rings are determined by the energy selective charging of the quantum ring distribution. The authors show, using conventional photocapacitance measurements, that the excess charge accumulated within the type-II nanostructures increases with increasing excitation energies for photon energies above 0.9 eV. Optical excitation between the localized hole states and the conduction band is therefore not limited to the Γ(k = 0) point, with pseudo-monochromatic light charging all states lying within the photon energy selected. The energy distribution of the quantum ring states could consequently be accurately related from the excitation dependence of the integrated photocapacitance. The resulting band of localized hole states is shown to be well described by a narrow distribution centered 407 meV above the GaAs valence band maximum.
U2 - 10.1063/1.4861129
DO - 10.1063/1.4861129
M3 - Journal article
VL - 115
JO - Journal of Applied Physics
JF - Journal of Applied Physics
SN - 0021-8979
IS - 1
M1 - 014302
ER -