MetaQD

Colloidal nanomaterials, and quantum dots in particular, have now reached sufficient maturity to explore concepts more complex than their use as absorbers/emitters, and should now be used as basic units for building functional heterostructures. Quantum dots have shown great potential for applications requiring optical gain, such as the development of miniaturized laser sources and light amplifiers. The MetaQD project aims to develop new colloidal metamaterials for optical gain, with the aim of demonstrating gain properties that are unattainable with a single-material approach. This project is based on the very high wavelength tunability of quantum dots and the high degree of control of their interfaces, opening up a wide range of possibilities for interaction between nanoparticles. In particular, the exploitation of inter-nanocrystal transitions could lead to the development of cascade structures, paving the way toward new efficient, miniaturized, infrared light sources. The MetaQD project will use advanced spectroscopic techniques to guide the development of such metamaterials. Such properties are desirable to address challenges for the integration of tunable and coherent light sources on photonic platforms. However, gain properties of these materials have been difficult to translate in electrically-injected devices. The MetaQD project will seek to probe optical gain in LED-like devices, in order to bring a higher degree of understanding of the charge injection processes in the high current regime. This original approach takes advantage of the project leader's experience in the field of colloidal optoelectronics, and is in line with the strong interdisciplinarity of the host laboratory 'Physique de la Matière Condensée' (PMC) at Ecole Polytechnique.