Plasmonically enhanced absorption in colloidal metal/semiconductor nanocomposites

Colloidal Quantum Dots (CQDs) are the route for low cost high eficiency photodetectors. Photoconductors are limited by the noise arising from high dark current densities, what is typically overcome reducing device's active area. However, this technique also reduces their photoresponse, and thei...

Full description

Bibliographic Details
Author: García de Arquer, Francisco Pelayo
Format: master thesis
Publication Date:2010
Country:España
Institution:Universitat Politècnica de Catalunya (UPC)
Repository:UPCommons. Portal del coneixement obert de la UPC
Language:English
OAI Identifier:oai:upcommons.upc.edu:2099.1/15369
Online Access:https://hdl.handle.net/2099.1/15369
Access Level:Open access
Keyword:Quantum dots
Optical detectors
Photoconductivity
colloidal quantum dots
photodetectors
plasmonic enhancement
Punts quàntics
Detectors òptics
Fotoconducció
Àrees temàtiques de la UPC::Enginyeria de la telecomunicació::Telecomunicació òptica::Fotònica
Description
Summary:Colloidal Quantum Dots (CQDs) are the route for low cost high eficiency photodetectors. Photoconductors are limited by the noise arising from high dark current densities, what is typically overcome reducing device's active area. However, this technique also reduces their photoresponse, and their optical absorption must be maintained as the volume is reduced. We study the use of plasmonics for that purpose, and present simulation results for solution-processed structures compatible with these techniques, showing up to a 13-fold enhancement in absorption. We present experimental results of a PbS CQDs photoconductor, fabricated using a novel CQDs functionalization, and venture the potential of these devices complemented with the shown promising techniques.