%0 Journal Article
%T Intrinsic dynamics of weakly and strongly confined excitons in nonpolar nitride-based heterostructures.
%+ Institute of Condensed Matter Physics [Lausanne]
%+ Departamento de Ingeniería Electrónica and ISOM (ETSI Telecomunicacion)
%+ Laboratoire Charles Coulomb (L2C)
%+ Institute of High Pressure Physics [Warsaw] (IHPP)
%A Corfdir, Pierre
%A Levrat, J.
%A Dussaigne, Amélie
%A Lefebvre, Pierre
%A Teisseyre, H.
%A Grzegory, Izabella
%A Suski, Tadeusz
%A Ganière, Jean-Daniel
%A Grandjean, N.
%A Deveaud-Plédran, Benoit
%Z Swiss National Science Foundation : Projects No. 129715 and 112294. Polish Ministry of Science and Higher Education: Project No. NN202 010134. European Regional Development Fund: Innovative Economy Grant No. POIG.01.01.02-00-008/08
%< avec comité de lecture
%@ 1098-0121
%J Physical Review B: Condensed Matter and Materials Physics (1998-2015)
%I American Physical Society
%V 83
%N 24
%P 245326
%8 2011-06-30
%D 2011
%R 10.1103/PhysRevB.83.245326
%Z PACS number(s): 78.47.jd, 78.55.Cr, 78.60.Hk, 78.67.De
%Z Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Journal articles
%X Both weakly and strongly confined excitons are studied by time-resolved photoluminescence in a nonpolar nitride-based heterostructure grown by molecular beam epitaxy on the a-facet of a bulk GaN crystal, with an ultralow dislocation density of 2 × 105 cm−2. Strong confinement is obtained in a 4 nm thick Al0.06Ga0.94N/GaN quantum well (QW), whereas weakly confined exciton-polaritons are observed in a 200 nm thick GaN epilayer. Thanks to the low dislocation density, the effective lifetime of strongly confined excitons increases between 10 and 150 K, proving the domination of radiative recombination processes. Above 150 K theQWemission lifetime diminishes, whereas the decay time of excitons in the barriers increases, until both barrier and QW exciton populations become fully thermalized at 300 K. We conclude that the radiative efficiency of our GaN QW at 300 K is limited by nonradiative recombinations in the barriers. The increase of exciton-polariton coherence lengths caused by low dislocation densities allows us to observe and model the quantized emission modes in the 200 nm nonpolar GaN layer. Finally, the low-temperature phonon-assisted relaxation mechanisms of such center-of-mass quantized exciton-polaritons are described.
%G English
%2 https://hal.science/hal-00631188/document
%2 https://hal.science/hal-00631188/file/PhysRevB.83.245326.pdf
%L hal-00631188
%U https://hal.science/hal-00631188
%~ CNRS
%~ L2C
%~ MIPS
%~ UNIV-MONTPELLIER
%~ UM-2015-2021