Proceedings of nanoGe Fall Meeting19 (NFM19)
DOI: https://doi.org/10.29363/nanoge.nfm.2019.349
Publication date: 18th July 2019
Excitonic interactions in 2D semiconductors garner considerable attention, both due to their relevance in quantum opto-electronics and to the richness of their physics. Quantum-well like derivatives of organicinorganic perovskites are emerging material systems where strongly bound two-dimensional excitons have been observed even at room temperature. Here, we identify and quantify the photophysical factors that govern the multi-body interactions in phenylethylammonium lead iodide, a prototypical 2D perovskite. Employing high-sensitivity coherent non-linear spectroscopy, we measure the homogenous linewidth of multiple excitonic transitions1. By following the evolution of the linewidths with temperature and excitation density, we obtain pertinent insights into the exciton-phonon and exciton-exciton interactions. Based on our recent work2-4, we also argue that polaronic effects are manifested intrinsically in the exciton spectral structure and point to the apparently deterministic role of polaronic effects in excitonic properties.
References
1. F. Thouin, D. Cortecchia, A. Petrozza, A. R. Srimath Kandada and C. Silva, Enhanced screening and spectral diversity in many-body elastic scattering of excitons in two-dimensional hybrid metalhalide perovskites, arXiv:1904.12402[cond-mat.mtrl-sci]. 2. A. R. Srimath Kandada and C. Silva, Perspective: Exciton polarons in two-dimensional hybrid metal-halide perovskites, arXiv:1908.03909[cond-mat.mtrl-sci]. 3. F. Thouin, A. R. Srimath Kandada, D. Valverde-Chavez, D. Cortecchia, I. Bargigia, A. Petrozza, X. Yang, E. R. Bittner and C. Silva, Electron-phonon couplings inherent in polarons drive exciton dynamics in two-dimensional metal-halide perovskites, Chem. Mater., DOI: 10.1021/acs.chemmater.9b02267. 4. F. Thouin, D. Valverde-Chavez, C. Quarti, D. Cortecchia, I. Bargigia, D. Beljonne, A. Petrozza, C. Silva and A. R. Srimath Kandada, Phonon coherences reveal the polaronic character of the excitons in two-dimensional lead-halide perovskites, Nature Materials 18, 349-356.