Repository logo
 

Polaronic Mass Enhancement and Polaronic Excitons in Metal Halide Perovskites

Published version
Peer-reviewed

Repository DOI


Type

Article

Change log

Authors

Baranowski, Michal 
Nowok, Andrzej 
Galkowski, Krzysztof 
Dyksik, Mateusz 
Surrente, Alessandro 

Abstract

In metal halide perovskites the complex dielectric screening together with low energy of phonon modes leads to non-negligible Fr¨ohlich coupling. While this feature of perovskites has been already used to explain some of the puzzling aspects of carrier transport in these materials, the possible impact of polaronic effects on the optical response, especially excitonic properties, is much less explored. Here with the use of magneto-optical spectroscopy, we revealed the non-hydrogenic character of the excitons in metal halide perovskites, resulting from the pronounced Fr¨ohlich coupling. Our results can be well described by the polaronic-exciton picture where electron and hole interaction are no longer described by a Coulomb potential. Furthermore, we show experimental evidence that the carrier-phonon interaction leads to the enhancement of the carrier’s effective mass. Notably, our measurements reveal a pronounced temperature dependence of the carrier’s effective mass, which we attribute to a band structure renormalization induced by the population of low-energy phonon modes. This interpretation finds support in our first-principles calculations.

Description

Keywords

34 Chemical Sciences, 3406 Physical Chemistry

Journal Title

ACS Energy Letters

Conference Name

Journal ISSN

2380-8195
2380-8195

Volume Title

Publisher

American Chemical Society
Sponsorship
Royal Society (UF150033)

Version History

Now showing 1 - 2 of 2
VersionDateSummary
2*
2024-07-18 12:50:43
Published version added
2024-05-21 23:31:43
* Selected version