skip to main content

SciTech ConnectSciTech Connect

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

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.
Authors:
; ; ; ; ; ;  [1] ;  [1] ;  [2]
  1. National Institute for Materials Science, Tsukuba, Ibaraki 305-0047 (Japan)
  2. (Japan)
Publication Date:
OSTI Identifier:
22258598
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 104; Journal Issue: 12; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABSORPTION; ALUMINIUM ARSENIDES; ELECTRIC POTENTIAL; GALLIUM ARSENIDES; QUANTUM WELLS; SOLAR CELLS