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This content will become publicly available on April 28, 2018

Title: Apparent bandgap shift in the internal quantum efficiency for solar cells with back reflectors

Here, we demonstrate that in solar cells with highly reflective back mirrors, the measured internal quantum efficiency exhibits a shift in bandgap relative to the measured external quantum efficiency. The shift arises from the fact that the measured reflectance at the front surface includes a superposition of waves reflecting from the front and back surfaces. We quantify the magnitude of the apparent shift and discuss the errors that can result in determination of quantities such as the photocurrent. Because of this apparent shift, it is important that the bandgap be determined from the external quantum efficiency.
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  1. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  2. Tau Science Corp., Hillsboro, OR (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0021-8979; JAPIAU
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 121; Journal Issue: 16; Journal ID: ISSN 0021-8979
American Institute of Physics (AIP)
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
Country of Publication:
United States
14 SOLAR ENERGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; band gap; III-V semiconductors; solar cell efficiency; photoelectric conversion; photons
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1361856