Recombination dynamics of free and bound excitons in bulk GaN
2008 (English)In: Superlattices and Microstructures, ISSN 0749-6036, Vol. 43, no 5-6, 610-614 p.Article in journal (Refereed) Published
We report new data on the transient photoluminescence behaviour of free and donor bound excitons in high quality bulk GaN material grown by HVPE. With 266 nm photoexcitation the no-phonon free exciton has a short decay time, about 100 ps at 2 K, assigned to nonradiative surface recombination. The LO replicas of the free exciton have a much longer decay at 2 K, about 1.4 ns, believed to be a lower bound for the bulk radiative lifetimes of the free excitons at 2 K. The donor bound exciton no-phonon lines exhibit a rather short (about 300 ps) nonexponential decay at 2 K, which appears to be dominated by a scattering process. The corresponding LO replicas and the two-electron transitions have a much longer decay. From the latter, the lower bound of the radiative lifetime of the O- and Si-bound excitons are 1800 ps and 1100 ps, respectively. © 2007 Elsevier Ltd. All rights reserved.
Place, publisher, year, edition, pages
2008. Vol. 43, no 5-6, 610-614 p.
Donors, Dynamics, Excitons, GaN, Recombination
National CategoryEngineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-46322DOI: 10.1016/j.spmi.2007.06.011OAI: oai:DiVA.org:liu-46322DiVA: diva2:267218