Iwan Moreels - PHOCONA

Iwan Moreels

Description of the PI

My work is focused on colloidal semiconductor nanocrystals (NCs), particles small enough that their opto-electronic properties can be controlled by varying the size, shape and material composition. This is made possible due to quantum confinement of electrons and holes within the NCs; they are therefore also referred to as quantum dots.
I did my PhD studies (2004-2009) under supervision of prof. Zeger Hens, in the Physics and Chemistry of Nanostructures group at Ghent University, studying the chemical synthesis of near-infrared PbS and PbSe NCs and their integration into silicon-on-insulator photonic devices. After the PhD, I turned to the investigation of the opto-electronic band structure and stimulated emission properties of CdSe-based quantum dots and quantum rods (2009-2011). The project was executed at Ghent university and the IBM Zurich Research Laboratory, Switzerland. In January 2012 I joined the Italian Institute of Technology (IIT), where I combined materials science and optical spectroscopy to design new photonic NCs. I became a tenure track researcher and set up the Nanocrystal Photonics Lab in 2014. In 2017 I returned to Ghent University as associate professor at the Department of Chemistry, continuing my work on the synthesis of 2D nanocrystals.



Description of the project

In PHOCONA we aim to develop a new class of highly fluorescent 2D and quasi-2D colloidal nanomaterials for solution-processed coherent light sources and ultrafast single-photon emitters. The 2D excitons are created in suspended semiconductor nanoplates with a thickness below 5 nm, and transition-metal dichalcogenide monolayers. Prepared by colloidal chemistry and liquid-phase exfoliation, respectively, they take advantage of both quantum confinement through their nanoscale dimensions, as well as dielectric confinement via the dielectric mismatch between nanomaterials and surrounding matrix. Via smart nanocrystal design, more specifically by exploiting novel synthesis methods that include asymmetric in-plane confinement potentials, anisotropic crystal structures, and lattice strain-induced band structure modifications in core/shell heterostructures,  the nanomaterials will be shaped toward efficient multiexciton and stimulated emission, as well as stable, blinking-free single-photon emission. The intrinsic 2D exciton properties will be further modified toward ultrafast exciton recombination by coupling the nanomaterials to small mode-volume plasmonic nanocavities, hereby placing them in a local photon density-of-states that will lead to a strong Purcell enhancement. The realization of cost-effective, energy-efficient and highly flexible light emitters, which can be synthesized and processed via methods that are scalable to large areas and volumes, forms an important milestone in the ongoing development of optical and quantum communications technology, as well as new lighting and display applications.