GaN nanorods grown on Si (111) substrates and exciton localization
1 Department of Semiconductor Science, Dongguk University, Seoul, 100-715, South Korea
2 Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
3 Quantum Functional Semiconductor Research Center, Dongguk University, Seoul, 100-715, South Korea
Nanoscale Research Letters 2011, 6:81 doi:10.1186/1556-276X-6-81Published: 12 January 2011
We have investigated exciton localization in binary GaN nanorods using micro- and time-resolved photoluminescence measurements. The temperature dependence of the photoluminescence has been measured, and several phonon replicas have been observed at the lower energy side of the exciton bound to basal stacking faults (I1). By analyzing the Huang-Rhys parameters as a function of temperature, deduced from the phonon replica intensities, we have found that the excitons are strongly localized in the lower energy tails. The lifetimes of the I1 and I2 transitions were measured to be < 100 ps due to enhanced surface recombination.
PACS: 78.47.+p, 78.55.-m, 78.55.Cr, 78.66.-w, 78.66.Fd