Electronic structure of GaNP alloys: Insights from optical studies
2003 (English)In: 204th Annual Meeting of the Electrochemical Society,2003, Proceedings - Electrochemical Society, Vol. 11: Electrochemical Society , 2003, 390-399 p.Conference paper (Other academic)
In this paper we review our recent results from optical studies that have provided new insights into the N-induced modifications of the electronic structure of GaNP alloys. The near-band gap photoluminescence (PL) in the alloys is attributed to excitonic transitions at localized states likely related to N clusters. Their energy levels positions are found to be insensitive to N composition and thus unlikely contribute to the formation of the conduction band (CB) states in the alloys. Experimental evidence for a band crossover from an indirect to a direct band gap in GaNP at very low N compositions (∼0.5%) is provided from transient PL studies and absorption measurements. Admixing of the localized states with the extended CB states during alloy formation is shown to have counteracting effects on the temperature variation of the band gap of the GaNP alloys after the band crossover. It is also demonstrated that post-growth hydrogen implantation can reverse the N-induced effects.
Place, publisher, year, edition, pages
Proceedings - Electrochemical Society, Vol. 11: Electrochemical Society , 2003. 390-399 p.
IdentifiersURN: urn:nbn:se:liu:diva-45057Local ID: 79501OAI: oai:DiVA.org:liu-45057DiVA: diva2:265919