Evidence of large polarons in photoemission band mapping of the perovskite semiconductor CsPbBr3
Creators
-
Puppin, Michele1
*
- Polishchuk, Serhii1
-
Colonna, Nicola2
*
- Crepaldi, Alberto3
- Dirin, Dmitry4, 5
- Nazarenko, Olga4, 5
-
De Gennaro, Riccardo2
*
- Gatti, Gianmarco3
- Roth, Silvan3
- Barillot, Thomas1
- Poletto, Luca6
- Xian, Rui Patrick7
- Rettig, Laurenz7
- Wolf, Martin7
- Ernstorfer, Ralph7
- Kovalenko, Maksym V.4, 5
-
Marzari, Nicola2
*
-
Grioni, Marco3
*
-
Chergui, Majed1
*
- 1. Laboratoire de Spectroscopie Ultrarapide and Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne, ISIC, Station 6, CH-1015 Lausanne, Switzerland
- 2. Theory and Simulations of Materials (THEOS), and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
- 3. Institute of Physics and Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
- 4. Laboratory of Inorganic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland
- 5. Laboratory for Thin Films and Photovoltaics, EMPA Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
- 6. National Research Council of Italy—Institute of Photonics and Nanotechnologies (CNR-IFN), via Trasea 7, 35131 Padova, Italy
- 7. Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
* Contact person
Description
Lead-halide perovskite (LHP) semiconductors are emergent optoelectronic materials with outstanding transport properties which are not yet fully understood. We find signatures of large polaron formation in the electronic structure of the inorganic LHP CsPbBr3 by means of angle-resolved photoelectron spectroscopy. The experimental valence band dispersion shows a hole effective mass of 0.26±0.02 me, 50% heavier than the bare mass m0=0.17 me predicted by ab-initio calculations. Calculations of the electron-phonon coupling indicate that phonon dressing of the carriers mainly occurs via distortions of the Pb-Br bond with a Fröhlich coupling parameter α=1.82. A good agreement between theoretical and experimental data is obtained within the Feynman polaron model, validating a viable theoretical method to predict the carrier effective mass of LHPs ab initio.
Files
File preview
files_description.md
All files
References
Journal reference (Paper where the data is discussed) M. Puppin, S. Polishchuk, N. Colonna, A. Crepaldi, D. N. Dirin, O. Nazarenko, R. De Gennaro, G. Gatti, S. Roth, T. Barillot, L. Poletto, R. P. Xian, L. Rettig, M. Wolf, R. Ernstorfer, M. V. Kovalenko, N. Marzari, M. Grioni, M. Chergui, Phys. Rev. Lett. 124, 206402 (2020), doi: 10.1103/PhysRevLett.124.206402
Preprint (Preprint of the paper where the data is discussed) M. Puppin, S. Polishchuk, N. Colonna, A. Crepaldi, D. N. Dirin, O. Nazarenko, R. De Gennaro, G. Gatti, S. Roth, T. Barillot, L. Poletto, R. P. Xian, L. Rettig, M. Wolf, R. Ernstorfer, M. V. Kovalenko, N. Marzari, M. Grioni, M. Chergui, arXiv:1909.00248v1