Photoluminescence plasmonic enhancement in InAs quantum dots coupled to gold nanoparticles

Photoluminescence enhancement due to dipole field from gold nanoparticles was observed at 77 K for GaAs capped InAs quantum dots. The gold nanoparticles were coupled to the surface of the cap layer by using dithiol ligands. The enhancement was investigated as a function of the GaAs capped layer thickness. An order of magnitude enhancement in the emission was observed in samples with a cap thickness of 12 nm. This enhancement however is drastically decreased in samples with a cap thickness of 200 nm. The observed enhancement is interpreted in terms of photon scattering from the large dipole scattering cross section. (C) 2011 Elsevier B.V. All rights reserved.