Long delays of light in ZnO caused by exciton-polariton propagation
2012 (English)In: Physica status solidi. B, Basic research, ISSN 0370-1972, E-ISSN 1521-3951, Vol. 249, no 7, 1307-1311 p.Article in journal (Refereed) Published
We study the propagation of exciton-polaritons through bulk ZnO using time-resolved photoluminescence (PL) complemented by time-of-flight measurements of laser pulses. When the photon energy approaches donor bound exciton resonances, substantial time delays in PL light propagation are observed which reach up to 210 ps for a 0.55 mm thick crystal. By comparing results from time-of-flight measurements performed using PL light and laser pulses, the observed delay is shown to be due to the formation of exciton-polaritons and their spectral dispersion. It is also shown that the main contribution to the slow-down effect arises from free exciton-polaritons, whereas bound exciton-polaritons become important only in close vicinity to the corresponding resonances.
Place, publisher, year, edition, pages
Wiley-VCH Verlagsgesellschaft, 2012. Vol. 249, no 7, 1307-1311 p.
excitons; polaritons; slow light; time-of-flight measurements; zinc oxide
Natural Sciences Condensed Matter Physics
IdentifiersURN: urn:nbn:se:liu:diva-74670DOI: 10.1002/pssb.201147559ISI: 000305966600001OAI: oai:DiVA.org:liu-74670DiVA: diva2:489928