Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1515069 | Energy Procedia | 2010 | 8 Pages |
Abstract
Prototypes based on InAs/GaAs QDs have been manufactured in order to realize the theoretically predicted high efficiency intermediate band solar cells (IBSCs). Unfortunately, until now, these prototypes have not yet demonstrated the expected increase in efficiency when compared with reference samples without IB material. One of the main arguments explaining this performance is the weak photon absorption in the QD-IB material, arising from a low density of QDs. In this work, we have analyzed the absorption coefficient of the IB material by developing a sample in an optical wave-guided configuration. This configuration allows us to illuminate the QDs laterally, increasing the path length for photon absorption. Using a multi-section metal contact device design, we were able to measure an absorption coefficient of â¼100 cmâ1 around the band edge (â¼1 eV ) defined by the V Bâ¦IB transition in InAs/GaAs QD-IB materials. This figure, and its influence on the IBSC concept, is analyzed for this system.
Related Topics
Physical Sciences and Engineering
Energy
Energy (General)
Authors
E. Cánovas, A. MartÃ, A. Luque, C.D. Farmer, C.R. Stanley, A.M. Sánchez, T. Ben, S.I. Molina,