GaAs quantum dot solar cell under concentrated radiation

Journal Article · Mon Aug 17 04:00:00 EDT 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4928669· OSTI ID:22489130

Sablon, K.; Little, J. W.; Hier, H. ^[1]; Li, Y.; Mitin, V. ^[2]; Vagidov, N. ^[2]; Sergeev, A. ^[1]

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1. U.S. Army Research Laboratory, Adelphi, Maryland 20783 (United States)
2. EE Department, University at Buffalo - SUNY, Buffalo, New York 14260 (United States)

Effects of concentrated solar radiation on photovoltaic performance are investigated in well-developed GaAs quantum dot (QD) solar cells with 1-Sun efficiencies of 18%–19%. In these devices, the conversion processes are enhanced by nanoscale potential barriers and/or AlGaAs atomically thin barriers around QDs, which prevent photoelectron capture to QDs. Under concentrated radiation, the short circuit current increases proportionally to the concentration and the open circuit voltage shows the logarithmic increase. In the range up to hundred Suns, the contributions of QDs to the photocurrent are proportional to the light concentration. The ideality factors of 1.1–1.3 found from the V{sub OC}-Sun characteristics demonstrate effective suppression of recombination processes in barrier-separated QDs. The conversion efficiency shows the wide maximum in the range of 40–90 Suns and reaches 21.6%. Detailed analysis of I-V-Sun characteristics shows that at low intensities, the series resistance decreases inversely proportional to the concentration and, at ∼40 Suns, reaches the plateau determined mainly by the front contact resistance. Improvement of contact resistance would increase efficiency to above 24% at thousand Suns.

• OSTI ID: 22489130
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 7 Vol. 107; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALUMINIUM ARSENIDES
ELECTRIC POTENTIAL
ELECTRICAL FAULTS
GALLIUM ARSENIDES
PHOTOVOLTAIC EFFECT
POTENTIALS
QUANTUM DOTS
RECOMBINATION
SOLAR CELLS
SOLAR RADIATION
SUN
VISIBLE RADIATION