Exciton States in Wurtzite InGaN Coupled Quantum Dots
XIA Cong-Xin1, SHI Jun-Jie2, WEI Shu-Yi1
1Department of Physics, Henan Normal University, Xinxiang 453002
2State Key Laboratory for Mesoscopic Physics and School of Physics, Peking University, Beijing 100871
Exciton States in Wurtzite InGaN Coupled Quantum Dots
XIA Cong-Xin1;SHI Jun-Jie2;WEI Shu-Yi1
1Department of Physics, Henan Normal University, Xinxiang 453002
2State Key Laboratory for Mesoscopic Physics and School of Physics, Peking University, Beijing 100871
Abstract： Based on the effective-mass approximation, exciton states confined in wurtzite InxGa1-xN/GaN strained coupled quantum dots (QDs) are investigated, in which the strong built-in electric field effects due to the piezoelectricity and spontaneous polarization are considered. We find that the barrier thickness between the two QDs has a considerable influence on the exciton states and the interband optical transitions. If the barrier thickness is increased, the exciton binding energy is decreased, the emission wavelength is increased, and the electron--hole recombination rate is obviously reduced. Our theoretical results are in qualitative agreement with the experimental measurements.
2004, Vol. 21 
