Type
ArticleAuthors
Ferreira, A. C.Létoublon, A.
Paofai, S.
Raymond, S.
Ecolivet, C.
Rufflé, B.
Cordier, S.
Katan, C.
Saidaminov, Makhsud I.

Zhumekenov, A. A.
Bakr, Osman

Even, J.
Bourges, P.
KAUST Department
Functional Nanomaterials Lab (FuNL)KAUST Catalysis Center (KCC)
KAUST Solar Center (KSC)
Material Science and Engineering Program
Physical Science and Engineering (PSE) Division
Date
2018-08-22Preprint Posting Date
2018-01-26Permanent link to this record
http://hdl.handle.net/10754/627055
Metadata
Show full item recordAbstract
Much recent attention has been devoted towards unraveling the microscopic optoelectronic properties of hybrid organic-inorganic perovskites. Here we investigate by coherent inelastic neutron scattering spectroscopy and Brillouin light scattering, low frequency acoustic phonons in four different hybrid perovskite single crystals: MAPbBr3, FAPbBr3, MAPbI3, and α-FAPbI3 (MA: methylammonium, FA: formamidinium). We report a complete set of elastic constants characterized by a very soft shear modulus C44. Further, a tendency towards an incipient ferroelastic transition is observed in FAPbBr3. We observe a systematic lower sound group velocity in the technologically important iodide-based compounds compared to the bromide-based ones. The findings suggest that low thermal conductivity and hot phonon bottleneck phenomena are expected to be enhanced by low elastic stiffness, particularly in the case of the ultrasoft α-FAPbI3.Citation
Ferreira AC, Létoublon A, Paofai S, Raymond S, Ecolivet C, et al. (2018) Elastic Softness of Hybrid Lead Halide Perovskites. Physical Review Letters 121. Available: http://dx.doi.org/10.1103/PhysRevLett.121.085502.Sponsors
This project has received funding from the European Union’s Horizon 2020 programme, through a FET Open research and innovation action under the Grant agreement No. 687008. M. I. S. acknowledges the support of Banting Postdoctoral Fellowship Program, administered by the Government of Canada.Publisher
American Physical Society (APS)Journal
Physical Review LettersarXiv
1801.08701Additional Links
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.121.085502ae974a485f413a2113503eed53cd6c53
10.1103/PhysRevLett.121.085502