Visualization of Dynamic Polaronic Strain Fields in Hybrid Lead Halide Perovskites

التفاصيل البيبلوغرافية
العنوان: Visualization of Dynamic Polaronic Strain Fields in Hybrid Lead Halide Perovskites
المؤلفون: Guzelturk, B., Winkler, T., Van de Goor, T., Smith, M. D., Bourelle, S. A., Feldmann, S., Trigo, M., Teitelbaum, S., Steinrück, H-G., de la Pena, G. A., Alonso-Mori, R., Zhu, D., Sato, T., Karunadasa, H. I., Toney, M. F., Deschler, F., Lindenberg, A. M.
المصدر: Nature Materials (2021)
سنة النشر: 2020
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Materials Science, Condensed Matter - Mesoscale and Nanoscale Physics
الوصف: Excitation localization involving dynamic nanoscale distortions is a central aspect of photocatalysis, quantum materials and molecular optoelectronics. Experimental characterization of such distortions requires techniques sensitive to the formation of point-defect-like local structural rearrangements in real time. Here, we visualize excitation-induced strain fields in a prototypical member of the lead halide perovskites via femtosecond resolution diffuse x-ray scattering measurements. This enables momentum-resolved phonon spectroscopy of the locally-distorted structure and reveals radially-expanding nanometer-scale elastic strain fields associated with the formation and relaxation of polarons in photoexcited perovskites. Quantitative estimates of the magnitude and the shape of this polaronic distortion are obtained, providing direct insights into the debated dynamic structural distortions in these materials. Optical pump-probe reflection spectroscopy corroborates these results and shows how these large polaronic distortions transiently modify the carrier effective mass, providing a unified picture of the coupled structural and electronic dynamics that underlie the unique optoelectronic functionality of the hybrid perovskites.
Comment: 17 pages, 4 figures
نوع الوثيقة: Working Paper
DOI: 10.1038/s41563-020-00865-5
URL الوصول: http://arxiv.org/abs/2011.03103
رقم الأكسشن: edsarx.2011.03103
قاعدة البيانات: arXiv
الوصف
DOI:10.1038/s41563-020-00865-5