Cover Image

Cation tuning of polaron barriers in layered perovskites for optical spin lifetime control

Layered metal-halide perovskites (L-MHPs) form self-assembled quantum wells with strongly bound excitons and electron-phonon interactions that promote polaron formation. Due to spin-orbit coupling and Rashba-type spin-splitting of the electronic bands, spin-polarized excitons can be photoexcited wit...

Full description

Saved in:
Bibliographic Details
Main Authors: Romano, Valentino (Author) , Hörmann, Martin (Author) , Stadlbauer, Anna (Author) , Mosconi, Edoardo (Author) , Gregori, Luca (Author) , De Angelis, Filippo (Author) , Deschler, Felix (Author) , Cerullo, Giulio (Author) , Camargo, Franco V. A. (Author)
Format: Article (Journal)
Language:English
Published: September 12, 2025
In: ACS energy letters
Year: 2025, Volume: 10, Issue: 9
ISSN:2380-8195
DOI:10.1021/acsenergylett.5c01236
Online Access:Resolving-System, kostenfrei, Volltext: https://doi.org/10.1021/acsenergylett.5c01236
Get full text
Author Notes:Valentino Romano, Martin Hörmann, Anna Stadlbauer, Edoardo Mosconi, Luca Gregori, Filippo De Angelis, Felix Deschler, Giulio Cerullo, and Franco V. A. Camargo
Description
Summary:Layered metal-halide perovskites (L-MHPs) form self-assembled quantum wells with strongly bound excitons and electron-phonon interactions that promote polaron formation. Due to spin-orbit coupling and Rashba-type spin-splitting of the electronic bands, spin-polarized excitons can be photoexcited with circularly polarized light, making these materials promising in opto-spintronics. Recently, we have shown that photoexcitation with excess energy extends spin-lifetimes in (BA)2FAPb2I7 by over 2 orders of magnitude compared to resonant excitation and attributed this to polaron formation. Here, we study spin-lifetimes in L-MHPs with different A-site cations: (Hexa)2MAPb2I7, (Hexa)2FAPb2I7, (Hexa)2CsPb2I7 (Hexa: hexylammonium, MA: methylammonium, FA: formamidinium, Cs: cesium). We find that all studied materials exhibit vastly extended spin-lifetimes under excess-energy excitation, but that the polaron formation barrier is reduced with increasing polarity of the A-site cations. First-principles calculations show that (Hexa)2MAPb2I7 has the most stable polarons and (Hexa)2CsPb2I7, the least. Our findings demonstrate tuning of optically controlled exciton spin-lifetimes in L-MHPs through composition engineering, providing a pathway toward optimized materials for spintronics.
Item Description:Online veröffentlicht am: 31. August 2025
Gesehen am 16.03.2026
Physical Description:Online Resource
ISSN:2380-8195
DOI:10.1021/acsenergylett.5c01236

Similar Items