Proceedings of MATSUS Spring 2025 Conference (MATSUSSpring25)
DOI: https://doi.org/10.29363/nanoge.matsusspring.2025.025
Publication date: 16th December 2024
There is recent evidence that, upon polaron formation, excitonic interactions in bulk lead halide perovskites experience different dielectric screening at short and long distances.[1,2] Above the polaron radius, static dielectric screening prevails. Under the polaron radius, dynamic screening prevails instead.
Here we investigate how such non-hydrogenic interactions affect the electronic structure of excitons, trions and biexcitons in confined halide perovskites: nanoplatelets and nanocrystals. To do so we develop a theoretical model which accounts for the main physical factors in these systems: (i) quantum confinement, through k·p theory, (ii) dielectric confinement, through image charge methods, (iii) electronic correlations, through a variational Quantum Monte Carlo method, and (iv) polaronic interactions, through Haken-like potentials.
We show that trions are formed by an exciton plus an excess carrier orbiting at longer distances, which reveals a significant ionic character of the bond. Biexcitons are formed by two excitons with strong intra-exciton interactions, and weaker inter-exciton ones. Polaronic interactions lead to large binding energies for excitons, trions and biexcitons. These are in good agreement with experimental measurements of nanoplatelets and Ruddlesden-Popper perovskites.[3-5] For nanocrystals, however, biexciton binding energies are systematically smaller than experimental values. This suggests excitons and biexcitons polarize the lattice differently.
We acknowledge support from Grant No. PID2021-128659NB-I00, funded by Ministerio de Ciencia e Innovación (MCIN/AEI/10.13039/501100011033 and ERDF A way of
making Europe)
nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.
Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.
International Conference on Hybrid and Organic Photovoltaics
International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.
Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics
The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.
The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.