Periodic Reporting for period 1 - SUPERLASER (ROOM TEMPERATURE SUPERRADIANT PEROVSKITE LASERS)
Okres sprawozdawczy: 2024-09-01 do 2025-08-31
Phase 1 – Project Launch and Coordination (WP1):
The project officially began with its Kick-off Meeting on September 23–24, 2024, hosted by NCSR “Demokritos” (coordinator). This phase ensured alignment across partners, established management procedures, and secured compliance with EC regulations, budgetary, and contractual obligations.
Phase 2 – Predictive Design and Material Development (WP2, WP3):
This phase focused on predicting and developing over one million potential halide perovskite phases with strong Rashba spin–orbit coupling (SOC) and no critical raw materials. The University of Nottingham (UoN) implemented a hierarchical computational discovery framework combining machine learning (ML), atomistic modeling, and DFT simulations to rapidly assess structural stability and optoelectronic properties. A dataset of 80 representative phases was generated using molecular dynamics accelerated by ML, forming the basis for a predictive tolerance factor model capable of mapping stability and guiding synthesis for 996 novel compounds.
In parallel, Linköping University (LiU) developed inorganic charge-transport layers, such as ZnO, optimized for perfect energy-level matching with perovskite emitters. The National and Kapodistrian University of Athens (NKUA) designed both n-type (e.g. PEI dendrimers, TDPPQ derivatives) and p-type organic semiconductors (e.g. Spiro-OMeTAD and derivatives) as efficient electron and hole injection layers in PeLEDs, enabling improved charge balance and device stability.
Phase 3 – Superlattice Development and Superradiance Validation (WP4, WP5):
This phase focused on fabricating and characterizing superradiant perovskite superlattices using solution-based, low-temperature methods. NCSR “D” successfully grew large MAFAPbI₃ crystals, with and without Rb incorporation, via inverse temperature crystallization. Universitat Jaume I (INAM-UJI) explored complementary synthetic routes such as space confinement and antisolvent-assisted crystallization, achieving Sn-based 3D perovskite single crystals. EPFL produced 2D and quasi-2D superlattices atop 3D perovskite substrates using a solution-phase approach, supporting the development of ordered, defect-minimized structures.
To validate room-temperature superradiance, LiU installed a cryostat-integrated transient absorption spectroscopy setup, enabling measurements from 300 K to 10 K. A new optical coherence protocol based on femtosecond transient absorption spectroscopy was also established, providing a reliable means to detect and quantify superradiant emission and coherence dynamics in perovskite thin films.
Phase 4 – Device Design, Prototyping, and Sustainability Assessment (WP6, WP7):
In the final phase, IMEC fabricated prototype PeLED devices exhibiting ultra-fast response times and current densities exceeding 10⁴ A/cm², establishing the groundwork for electrically pumped superradiant perovskite lasers. These devices will integrate superlattice emitters from earlier phases with optimized organic/inorganic charge transport layers.
At the materials level, the project employs a machine-learning-accelerated computational framework that predicts the stability and phase behavior of mixed halide perovskites across vast compositional spaces. This hierarchical design approach establishes the first predictive rules for room-temperature superradiance, surpassing current empirical and low-temperature systems. Molecular dynamics–based phase stability models further enable precise control over structure, electronic coupling, and spin–orbit interactions—capabilities beyond existing simulation tools.
Experimentally, SUPERLASER pioneers the fabrication of continuous perovskite superlattices, eliminating interface-induced coherence loss seen in nanocrystal assemblies. These ordered structures sustain collective light–matter coupling over macroscopic scales, achieving room-temperature superradiance in a solid-state material. Femtosecond transient absorption spectroscopy integrated with cryogenic and ambient setups allows direct measurement of coherence lifetimes and emission dynamics with unprecedented precision.
In device engineering, the project develops advanced charge-transport materials and electrically pumped perovskite lasers capable of sub-nanosecond operation, combining high mobility, low non-radiative loss, and topologically protected emission. This represents a critical breakthrough toward sustainable, high-speed perovskite laser diodes.
Environmentally, SUPERLASER integrates life-cycle assessment (LCA) and circular design principles from the outset, minimizing e-waste and ensuring full recyclability—contrasting sharply with traditional, resource-intensive laser fabrication.