Carrier recombination effects in strain compensated quantum dot stacks embedded in solar cells

3 páginas, 3 figuras.
In this work we report the stacking of 50 InAs/GaAs quantum dot layers with a GaAs spacer thickness of 18 nm using GaP monolayers for strain compensation. We find a good structural and optical quality of the fabricated samples including a planar growth front across the whole structure, a reduction in the quantum dot size inhomogeneity, and an enhanced thermal stability of the emission. The optimized quantum dot stack has been embedded in a solar cell structure and we discuss the benefits and disadvantages of this approach for high efficiency photovoltaic applications.
The authors gratefully acknowledge financial support by the Spanish MEC and CAM through Projects 200560M089, S-05050/ENE-0310, TEC-2005-05781-C03-01, and -02, Consolider-Ingenio 2010 CSD2006-0004, the Junta de Andalucia (Project TEP383, Group TEP120), and by the European Commission through the SANDIE Network of Excellence (NMP4-CT-2004-500101).