Authors: Anita R Warrier Jayachandra Bingi C Vijayan
Publish Date: 2015/10/28
Volume: 11, Issue: 4, Pages: 953-961
Abstract
Excitonplasmon coupling can significantly modify the spectral response of semiconductor quantum dots in a metal nanoparticlesemiconductor complex system βIn2S3 quantum dots of size ∼3 nm and Ag nanospheres of size ∼100 nm were synthesized by chemical route and coated over glass substrates In the strong coupling regime the plasmons are shown to mediate indirect Coulomb interaction between the quantum dots In the proximity of Ag plasmons the excitonic binding energy of the βIn2S3 quantum dots increases by ∼500 meV indicating that the interaction potential between the quantum dots is positive and repulsive in nature This interaction also leads to strong coupling of the defect levels in the SQD complex The defect emission wavelength can be enhanced by an order of 102 or shifted from red region ∼650 nm to green ∼550 nm by controlling the plasmoninduced defect level coupling The experimental observation demonstrates one of the theoretically predicted consequences of excitonplasmon interaction This work demonstrates the possibility of harnessing the potential of the two complimentary systems semiconductor quantum dots and metal nanoparticles to achieve controllable emission and absorption properties for fabrication of nano plasmonic devices
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