Enhanced photoluminescence excitation in surface plasmon coupling with an InGaN/GaN quantum well

The authors report the observation of the enhancement of photoluminescence excitation through the couplings of an InGaN/GaN quantum well (QW) with localized surface plasmons (LSPs) and surface plasmon polaritons (SPPs), which are generated on a Ag nanostructure deposited on the SiN-coated QW epitaxial sample. At the wavelengths corresponding to the LSP modes, the excitation light is first absorbed by the LSPs. The LSP energy is then transferred into the QW such that the effective QW absorption is enhanced. Meanwhile, the application of the LSP local field to the QW may increase its absorption coefficient. Then, the coupling of the relaxed carriers with the SPPs enhances light emission that becomes stronger as temperature increases because of the increased carrier momentum. (C) 2007 American Institute of Physics.