GaAs/AlGaAs quantum wells with indirect-gap AlGaAs barriers for solar cell applications

Journal Article · Mon Mar 24 04:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4869148· OSTI ID:22258598

Otto, L. M.; Elborg, M.; Jo, M.; Mano, T.; Kawazu, T.; Han, L. ^[1]; Sakaki, H. ^[1]

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1. National Institute for Materials Science, Tsukuba, Ibaraki 305-0047 (Japan)

We have fabricated GaAs/AlGaAs quantum well (QW) solar cells in which 3 nm-thick QWs and indirect-gap Al{sub 0.78}Ga{sub 0.22}As barriers are embedded, and we studied extraction processes of photogenerated carriers in this QW system. The photocurrent under 700 nm light illumination at voltages close to the open-circuit voltage shows only a small reduction, indicating that the carrier recombination inside QWs is largely suppressed. We attribute this result to an efficient extraction of electrons from the QWs through the X-valley of AlGaAs. The insertion of QWs is shown to be effective in extending the absorption wavelengths and in enhancing the photocurrent. The use of indirect-gap materials as barriers is found to enhance carrier extraction processes, and result in an improved performance of QW solar cells.

• OSTI ID: 22258598
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 12 Vol. 104; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABSORPTION
ALUMINIUM ARSENIDES
ELECTRIC POTENTIAL
GALLIUM ARSENIDES
QUANTUM WELLS
SOLAR CELLS