ERC FUNDED PROJECTS

The aim of this project is the realisation of efficient mid-infrared and THz optoelectronic emitters. This work is motivated by the fact that the spontaneous emission in this frequency range is characterized by an extremely long lifetime when compared to non-radiative processes, giving rise to devices with very low quantum efficiency. To this end we want to develop hybrid light-matter systems, already well known in quantum optics, within optoelectronics devices, that will be driven by electrical injection. With this project we want to extend the field of optoelectronics by introducing some of the concepts of quantum optic, particularly the light-matter strong coupling, into semiconductor devices. More precisely this project aims at the implementation of novel optoelectronic emitters operating in the strong coupling regime between an intersubband excitation of a two-dimensional electron gas and a microcavity photonic mode. The quasiparticles issued from this coupling are called intersubband polaritons. The major difficulties and challenges of this project, do not lay in the observation of these quantum effects, but in their exploitation for a specific function, in particular an efficient electrical to optical conversion. To obtain efficient quantum emitters in the THz frequency range we will follow two different approaches: - In the first case we will try to exploit the additional characteristic time of the system introduced by the light-matter interaction in the strong (or ultra-strong) coupling regime. - The second approach will exploit the fact that, under certain conditions, intersubband polaritons have a bosonic character; as a consequence they can undergo stimulated scattering, giving rise to polaritons lasers as it has been shown for excitonic polaritons.

1 761 000 €

Start date: 2010-05-01, End date: 2015-04-30

Redox chemistry provides the fundamental basis for numerous energy-related electrochemical devices, among which Li-ion batteries (LIB) have become the premier energy storage technology for portable electronics and vehicle electrification. Throughout its history, LIB technology has relied on cationic redox reactions as the sole source of energy storage capacity. This is no longer true. In 2013 we demonstrated that Li-driven reversible formation of (O2)n peroxo-groups in new layered oxides led to extraordinary increases in energy storage capacity. This finding, which is receiving worldwide attention, represents a transformational approach for creating advanced energy materials for not only energy storage, but also water splitting applications as both involve peroxo species. However, as is often the case with new discoveries, the fundamental science at work needs to be rationalized and understood. Specifically, what are the mechanisms for ion and electron transport in these Li-driven anionic redox reactions? To address these seminal questions and to widen the spectrum of materials (transition metal and anion) showing anionic redox chemistry, we propose a comprehensive research program that combines experimental and computational methods. The experimental methods include structural and electrochemical analyses (both ex-situ and in-situ), and computational modeling will be based on first-principles DFT for identifying the fundamental processes that enable anionic redox activity. The knowledge gained from these studies, in combination with our expertise in inorganic synthesis, will enable us to design a new generation of Li-ion battery materials that exhibit substantial increases (20 -30%) in energy storage capacity, with additional impacts on the development of Na-ion batteries and the design of water splitting catalysts, with the feasibility to surpass current water splitting efficiencies via novel (O2)n-based electrocatalysts.

2 249 196 €

Start date: 2015-10-01, End date: 2021-03-31

Diabetes has become one of the most widespread metabolic disorders with epidemic dimensions affecting almost 6% of the world’s population. Despite modern treatments, the life expectancy of patients with Type 1 diabetes remains reduced as compared to healthy subjects. There is therefore a need for alternative therapies. Towards this aim, using the mouse, we recently demonstrated that the in vivo forced expression of a single factor in pancreatic alpha-cells is sufficient to induce a continuous regeneration of alpha-cells and their subsequent conversion into beta-like cells, such converted cells being capable of reversing the consequences of chemically-induced diabetes in vivo (Collombat et al. Cell, 2009). The PI and his team therefore propose to further decipher the mechanisms involved in this alpha-cell-mediated beta-cell regeneration process and determine whether this approach may be applied to adult animals and whether it would efficiently reverse Type 1 diabetes. Furthermore, a major effort will be made to verify whether our findings could be translated to human. Specifically, we will use a tri-partite approach to address the following issues: (1) Can the in vivo alpha-cell-mediated beta-cell regeneration be induced in adults mice? What would be the genetic determinants involved? (2) Can alpha-cell-mediated beta-cell regeneration reverse diabetes in the NOD Type 1 diabetes mouse model? (3) Can adult human alpha-cells be converted into beta-like cells? Together, these ambitious objectives will most certainly allow us to gain new insight into the mechanisms defining the identity and the reprogramming capabilities of mouse and human endocrine cells and may thereby open new avenues for the treatment of diabetes. Similarly, the determination of the molecular triggers implicated in the beta-cell regeneration observed in our diabetic mice may lead to exciting new findings, including the identification of “drugable” targets of importance for human diabetic patients.

1 500 000 €

Start date: 2012-01-01, End date: 2016-12-31

Imaging is one of the most powerful technique to visualize molecules, tissues, to understand and follow processes and it is the most used diagnostic tool in vitro and in vivo, Current biomedical imaging techniques can have high sensitivity, good spatial/temporal resolution and, in some cases, high tissue penetration but cannot combine all of these desired properties without using harmful radiations (or toxic labels) or very expensive equipment. Optical imaging techniques represent the best compromise among them; however, their ability to scale to human body is precluded. The main restriction of fluorescence imaging is that it requires light excitation which is limited by tissue absorption and scattering. Such limitations are not present in chemiluminescence imaging since light production occurs through a chemical reaction, resulting in higher penetration depth and best sensitivity. However both natural and artificial chemiluminescent systems require a continuous flow of exogenous reactants since all substrates are irreversibly consumed. BioPoweredCL aims to develop an unprecedented strategy to enable molecular imaging by realizing near infrared luminophores that harvest energy from the cellular respiration chain, in order to emit light without being consumed themselves. BioPoweredCL takes advantage of the most recent progress in artificial light production to develop a novel imaging technique where the absence of an excitation source overcomes the current limitations of fluorescence imaging while the regeneration of the luminophore overcomes the limitations of bioluminescence imaging. If successful it could replace current techniques based on harmful ionizing radiations such as X-rays or γ-rays. To reach such a grand-challenge the work plan is articulated into three different phases: 1) synthesis of new luminophores; 2) electrochemical characterization and energy cell harvesting; 3) in vitro experiments where the full potential of the approach will be validated.

1 449 750 €

Start date: 2021-10-01, End date: 2026-09-30