27 January 2023
The paper describes the first ultrafast direct measurement of structural dynamics and heat release under high excitation in 2D perovskites. These materials are used in highly efficient perovskite (...)
5 December 2022
The jury of the French Physical Society (SFP) Grand Prix has awarded the Jean Ricard Prize 2022 to Jacky EVEN, professor at INSA Rennes, physicist at the UMR Institut FOTON, and senior member of (...)
26 September 2022
(Science 2022) Realizing solution-processed heterostructures is a long-enduring challenge in halide perovskites because of solvent incompatibilities that disrupt the underlying layer. By solvent fine tuning, we could grow phase-pure two-dimensional (2D) halide perovskite bilayer stacks of the desired composition, thickness, and bandgap onto 3D perovskites without dissolving the underlying substrate. Thickness dependence of the 2D perovskite layer reveals the anticipated trends for n-i-p and p-i-n architectures, which is consistent with band alignment and carrier transport limits for 2D perovskites. We measured a photovoltaic efficiency of 24.5%, with exceptional stability of T99 (time during which the efficiency remains above 99% of its initial value) of >2000 hours, implying that the 3D/2D bilayer inherits the intrinsic durability of 2D perovskite without compromising efficiency.
9 September 2022
(Science 2022) Colloidal lead halide perovskite nanocrystals are of interest as photoluminescent quantum dots (QDs) whose properties depend on their size and shape. We report a room-temperature synthesis of monodisperse, isolable, spheroidal APbBr3 QDs (“A” indicates cesium, formamidinium, and methylammonium) that are size tunable from 3 to >13 nanometers. The kinetics of both nucleation and growth are temporally separated and substantially slowed down. QDs of all these compositions exhibit up to four excitonic transitions in their linear absorption spectra, and we demonstrate experimentally and theoretically that the size-dependent confinement energy for all transitions is independent of the A-site cation.
17 February 2021
Since September 2020, the Foton Institute has been welcoming two visual artists as part of an Art & Science residency within the laboratory (...)
3 February 2020
(Physical Review Letters, mar. 2016) The introduction of a slow-light medium in an optical micro-resonator extends the lifetime of a photon circulating in the device by several orders of magnitude.
15 December 2022
« Development of new materials for solar hydrogen production », Thursday 15 December 2022, 1:00 pm, , INSA Rennes (...)
16 December 2021
« Hybrid photonic integrated circuits based on porous silicon and polymers for biosensor applications », Thursday 16th of december 2021, 10:00 am, ENSSAT (...)
12 July 2021
« Contribution to the study of the non-linear properties of chalcogenide glass waveguides and micro-resonators », Monday 12th july 2021, 10:00 am, videoconferencing (...)
15 June 2021
« Optoelectronic, vibrational and transport properties of III-V/Si antiphase boundaries for photonics and solar energy harvesting », Tuesday 15th june 2021, 9:30 am, INSA Rennes (...)
17 February 2021
« Optical Signal Processing for Space Division Multiplexed Systems », Wednesday 17th of february 2021, 9:00 am, ENSSAT (...)
By combining cryogenic single-QD photoluminescence spectroscopy with configuration-interaction (...)
We settle the debate on the bright-dark exciton level ordering in these materials. We show (...)
Jacky EVEN and his coauthors received the award of the best fundamental contribution for the (...)
Every year, the Highly Cited Researchers™ list from Clarivate™ identifies scientists and social (...)
Marios ZACHARIAS, Post-doctoral researcher of FOTON-OHM (INSA) CNRS laboratory, received the (...)
In a recent collaborative work, a team of researchers from ISCR (Rennes), FOTON (Rennes), and (...)
(Nature Nanotechnology 2021) In this Review, a high enhancement of photovoltaic efficiency of 2D perovskite solar cells is presented. (...)
(Advanced Science 2021) In the work which has just been published in the prestigious journal “ Advanced Science ”, the Rennes team proposes to use a new family of materials with quite astonishing photoelectric properties to produce solar hydrogen efficiently, at low cost and with a low environmental impact. This proposal is accompanied by several demonstrations of photoelectrodes operating under solar illumination. (...)
About the European COST action OPERA The European network COST OPERA "European Network for (...)
We report efficient, regenerative and low-cost electron sources based on solution-processed (...)
