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SUMMARY:TYC Soiree: Many-Body Theory Calculations on Materials - Marina Filip & Linn Leppert
DESCRIPTION:Venue: LG11\, Bentham House\,  \n\n\n\n\n\n \n\n\n\n\n\n\n\n\n\n\nTYC Soiree: Many-Body Theory Calculations on Materials – Marina Filip & Linn Leppert Share on X\n\n\n\n\nMarina Filip – University of OxfordExcitons in Heterogeneous Semiconductors from First Principles Computational Modeling: Impact of Ionic Vibrations\, Temperature\, Crystal Structure and Chemical CompositionUnderstanding the physics of how excitons form\, delocalize and dissociate is of key importance tothe functionality of a wide range of applications\, such as photovoltaics\, lighting and lasing.Development of new computational modeling techniques based on density functional theory (DFT)and many body perturbation theory capable to describe interactions between excitons and otherquasiparticles constitutes a frontier first principles computational modeling of materials. TheGW+Bethe-Salpeter Equation (BSE) approach [1\,2] is the state-of-the-art approach to computeoptical excitation energies in semiconductors and insulators and provides the foundation of newmethods aimed at describing complex excited state phenomena.In the first part of my talk\, I will present a new methodological development that generalizes theBSE to include the impact of ionic vibrations on the dielectric screening of excitons [3\,4]\, and showhow this allows us to compute temperature dependent exciton binding energies\, as well the rate ofdissociation of excitons upon scattering with phonons.In the second part of my talk (as time allows)\, I will present a recent study of exciton delocalizationin several heterogeneous semiconductors belonging to the broader family of halide perovskites. Iwill discuss our recent analysis of optical excitations in quasi-2D organic-inorganic halideperovskites [5-8]\, and show how subtle structural features can significantly impact thedelocalization of excitons in these systems. \n\n\n\n\nHybertsen & Louie\, Phys. Rev. B 34\, 5390 (1986).\n\n\n\nRohlfing & Louie\, Phys. Rev. Lett. 81\, 2312 (1998).\n\n\n\nFilip\, Haber & Neaton\, Phys. Rev. Lett. 127\, 67401 (2021).\n\n\n\nAlvertis\, Haber\, Li\, Coveney\, Louie\, Filip & Neaton\, submitted (2023)\, arXiv:2312.03841.\n\n\n\nCoveney\, Haber\, Alvertis\, Neaton & Louie\, submitted (2023).\n\n\n\nFilip\, Qiu\, Del Ben & Neaton\, Nano Lett. 22 (12)\, 4870-4878 (2022).\n\n\n\nMcArthur\, Filip & Qiu\, Nano Lett. 23 (9)\, 3796-3802 (2023).\n\n\n\nChen & Filip\, J. Phys. Chem. Lett. 14\, 47\, 10634-10641 (2023).\n\n\n\n\n \n\n\n\nLinn Leppert – University of TwenteA first-principles perovskites potpourri: Electronic and excited-state structure of double\, layered\, extended and non-perovskitesPerovskite solar cells in which methylammonium lead iodide is used as a solar absorber material\, have reached maturity in the last years owing to a concerted effort to optimize material synthesis\, stability\, and device performance. However\, the halide perovskite family features thousands of other stable members with highly tunable optoelectronic properties. In this presentation\, I will provide an overview of our current understanding of the electronic and excited-state structure of several classes of perovskites – double\, layered\, extended – as well as some perovskite-like structures (thrown in for good measure). We use Green’s function-based many-body perturbation theory in the GW and Bethe-Salpeter Equation approach to calculate accurate bandstructures [1\, 2]\, optical absorption spectra and excitonic properties from first principles. Our calculations allow us to map the complex landscape of electronic properties and excitons\, understand the impact of chemical heterogeneity [3 – 6]\, dimensionality [5 -7] and temperature effects [8]\, and provide chemically intuitive rules for when to trust canonical models for excitons in these materials. \n\n\n\n[1] L. Leppert\, T. Rangel\, J. Neaton\, Phys. Rev. Materials 2019\, 3\, 103803.[2] T. Lebeda\, T. Aschebrock\, J.Sun\, L. Leppert\, S. Kümmel\, Phys. Rev. Materials 2023\, 7\, 093803.[3] A. Slavney\, B. Connor\, L. Leppert\, H. Karunadasa\, Chem. Sci. 2019\, 10\, 11041.[4] R.-I. Biega\, M. Filip\, L. Leppert\, J. B. Neaton\, J. Phys. Chem. Lett. 2021\, 12\, 2057.[5] R.-I. Biega\, Y. Chen\, M. R. Filip\, L. Leppert\, Nano Lett. 2023\, 23\, 8155.[6] H. J. Jöbsis\, K. Fykouras\, J. Reinders\, J. van Katwijk\, J. Dorresteijn\, T. Arens\, I. Vollmer\, L. Muscarella\, L. Leppert\, E. M. Hutter\, Advanced Functional Materials 2023\, 2306106.[7] B. A. Connor\, L. Leppert\, M. D. Smith\, J. B. Neaton\, H. I. Karunadasa\, J. Am. Chem. Soc. 2018\, 140\, 5235.[8] S. Krach\, N. Forera-Correa\, R.-I. Biega\, S. E. Reyes-Lillo\, L. Leppert\, J. Phys. Condens. Matter 2023\, 35\, 174001.[9] B. A. Connor\, A. C. Su\, A. H. Slavney\, L. Leppert\, H. Karunadasa\, Chem. Sci. 2023\, accepted manuscript.[10] R.-I. Biega\, M. Bokdam\, K. Herrmann\, J. Mohanraj\, D. Skyrbek\, M. Thelakkat\, M. Retsch\, L. Leppert\, J. Phys. Chem. C 2023\, 127\, 9183. \n\n\n\nMarina R. Filip\, University of OxfordExcitons in Heterogeneous Semiconductors from First Principles Computational Modeling:Impact of Ionic Vibrations\, Temperature\, Crystal Structure and Chemical CompositionUnderstanding the physics of how excitons form\, delocalize and dissociate is of key importance tothe functionality of a wide range of applications\, such as photovoltaics\, lighting and lasing.Development of new computational modeling techniques based on density functional theory (DFT)and many body perturbation theory capable to describe interactions between excitons and otherquasiparticles constitutes a frontier first principles computational modeling of materials. TheGW+Bethe-Salpeter Equation (BSE) approach [1\,2] is the state-of-the-art approach to computeoptical excitation energies in semiconductors and insulators and provides the foundation of newmethods aimed at describing complex excited state phenomena.In the first part of my talk\, I will present a new methodological development that generalizes theBSE to include the impact of ionic vibrations on the dielectric screening of excitons [3\,4]\, and showhow this allows us to compute temperature dependent exciton binding energies\, as well the rate ofdissociation of excitons upon scattering with phonons.In the second part of my talk (as time allows)\, I will present a recent study of exciton delocalizationin several heterogeneous semiconductors belonging to the broader family of halide perovskites. Iwill discuss our recent analysis of optical excitations in quasi-2D organic-inorganic halideperovskites [5-8]\, and show how subtle structural features can significantly impact thedelocalization of excitons in these systems. \n\n\n\n\nHybertsen & Louie\, Phys. Rev. B 34\, 5390 (1986).\n\n\n\nRohlfing & Louie\, Phys. Rev. Lett. 81\, 2312 (1998).\n\n\n\nFilip\, Haber & Neaton\, Phys. Rev. Lett. 127\, 67401 (2021).\n\n\n\nAlvertis\, Haber\, Li\, Coveney\, Louie\, Filip & Neaton\, submitted (2023)\, arXiv:2312.03841.\n\n\n\nCoveney\, Haber\, Alvertis\, Neaton & Louie\, submitted (2023).\n\n\n\nFilip\, Qiu\, Del Ben & Neaton\, Nano Lett. 22 (12)\, 4870-4878 (2022).\n\n\n\nMcArthur\, Filip & Qiu\, Nano Lett. 23 (9)\, 3796-3802 (2023).\n\n\n\nChen & Filip\, J. Phys. Chem. Lett. 14\, 47\, 10634-10641 (2023).
URL:https://thomasyoungcentre.org/event/tyc-soiree-many-body-theory-calculations-on-materials-marina-filip-linn-lepert/
CATEGORIES:Main event
ORGANIZER;CN="Martijn Zwijnenburg":MAILTO:m.zwijnenburg@ucl.ac.uk
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