Accession Number : AD1022780

Title :   Encapsulating Quantum Dots into ZnO Nanorods for Advanced photonics and Laser Applications

Descriptive Note : Technical Report,16 Jun 2014,15 Jun 2016


Personal Author(s) : Motta, Nunzio

Full Text :

Report Date : 15 Sep 2016

Pagination or Media Count : 15

Abstract : Colloidal quantum dots are promising for new-generation light-emitting devices and lasers. By encapsulating quantum dots with various emission colours into single-crystal ZnO nano/microrods grown in chemical bath we obtain Fabry-Perot type resonances of the light emitted when stimulated by an external laser. The hexagonal structure of ZnO crystals act as optical cavity, and due to the waveguide effect partial photons would propagate along the nano/microrods axis direction. In order to grow patterned and ordered ZnO nano/microrodsfor Fabry-Perot type resonance, we developed a microsphere lithography technique to produce shadow masks onto GaN substrates. In this way we have been able to grow vertical ZnO nano/microrods arrays with controllable interspace and size by a simple aqueous solution method. We demonstrate the encapsulation of quantum dots (QD) into the ZnO nano/microrods by a regrowth process. The optical properties of the single rod, and of the ensemble of the structures are measured by photoluminescence, showing a clear enhancement of the light emitted by QD adsorbed on the rod surface, and a wavelength shift coupled to an intensity reduction after the encapsulation. This study is the first step towards the development of color-tunable lighting devices and lasers based on micro/nanorods, and will open the way to a plethora of applications in optoelectronics, medicine, and gas sensing.

Descriptors :   quantum dots , nanostructures , NANOFABRICATION , PHOTONICS , nanotechnology , LITHOGRAPHY (FABRICATION) , aqueous solutions , PHOTOLUMINESCENCE , single crystals , optical properties , EPITAXIAL GROWTH , RESONANCE

Subject Categories : Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE