Band gap reduction and dielectric function of Ga1-xZnxN1-xOx and In1-xZnxN1-xOx alloys
2012 (English)In: Physica Status Solidi. A: Applications and Materials Science (Print), ISSN 1862-6300, Vol. 209, no 1, 75-78 p.Article in journal (Refereed) Published
The band gap reductions, dielectric functions and absorption coefficients of the Ga1-xZnxN1-xOx and In1-xZnxN1-xOx (x=0.00, 0.25, 0.50, 0.75, and 1.00) alloys were calculated, employing the partial self-consistent GW approximation. As a comparison, the local density approximation (LDA) and the Heyd-Scueria-Ernzerhof (HSE) hybrid functional were also used to calculate the gap reduction. Both Ga1-xZnxN1-xOx and In1-xZnxN1-xOx alloys show strong band gap bowing. As a result, the band gap energy in Ga1-xZnxN1-xOx is reduced by E-g(GaN) E-g (Ga1-xZnxN1-xOx) - 1.61, 2.01 and 1.91 eV for x=0.25, 0.50, and 0.75, respectively. This allows optoelectronic devices based on GaN and ZnO with more efficient absorption or emission of light in the visible light range. The calculated dielectric functions and absorption spectra demonstrate that the band gap reduction enhances the optical absorption around the 2.5 eV region. Interestingly, the In1-xZnxN1-xOx alloy with x=0.25 has the large optical absorption coefficient in the energy region 0.69-6.0 eV, and the alloy has very good absorption at 2-3 eV.
Place, publisher, year, edition, pages
2012. Vol. 209, no 1, 75-78 p.
absorption, band gap, dielectric function, GaN, InN, semiconductor alloys, ZnO
IdentifiersURN: urn:nbn:se:kth:diva-95277DOI: 10.1002/pssa.201100148ISI: 000303380700015ScopusID: 2-s2.0-84055218396OAI: oai:DiVA.org:kth-95277DiVA: diva2:527646
FunderSwedish Research Council
QC 201205222012-05-222012-05-212015-04-23Bibliographically approved