High-absorption-efficiency superlattice solar cells by excitons

Jiro Nishinaga, Atsushi Kawaharazuka, Koji Onomitsu, Yoshiji Horikoshi

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)


The effect of excitonic absorption on solar cell efficiency has been investigated using solar cells with AlGaAs/GaAs superlattice structures. Numerical calculations reveal that excitonic absorption considerably enhances the overall absorption of bulk GaAs. Excitonic absorption shows strong and sharp peaks at the absorption edge and in the energy region above the band gap. Absorption enhancement is also achieved in the AlGaAs/GaAs superlattice. The measured quantum efficiency spectra of the superlattice solar cells are quite similar to the calculated absorption spectra considering the excitonic effect. The superlattice solar cells are confirmed to have high absorption coefficient compared with the GaAs and AlGaAs bulk solar cells. These results suggest that the enhanced absorption by excitons can increase the quantum efficiency of solar cells. This effect is more prominent for the solar cells with small absorption layer thicknesses.

Original languageEnglish
Article number112302
JournalJapanese Journal of Applied Physics
Issue number11 PART 1
Publication statusPublished - 2013 Nov

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)


Dive into the research topics of 'High-absorption-efficiency superlattice solar cells by excitons'. Together they form a unique fingerprint.

Cite this