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Updated: Dec 17, 2025
Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance
Published on: February 27, 2017
How Exciton Interactions Control Spin-Depolarization in Layered Hybrid Perovskites
Sean A Bourelle1, Ravichandran Shivanna1, Franco V A Camargo2
1Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom.
Abstract:
Using circularly polarized broadband transient absorption, time-resolved circular photoluminescence, and transient Faraday rotation spectroscopy, we report that spin-dependent interactions have a significant impact on exciton energies and spin depolarization times in layered Ruddlesden-Popper hybrid metal-halide perovskites. In BA2FAPb2I7, we report that room-temperature spin lifetimes are largest (3.2 ps) at a carrier density of ∼1017 cm-3 with increasing depolarization rates at higher exciton densities. This indicates that many-body interactions reduce spin-lifetimes and outcompete the effect of D'yakonov-Perel precessional relaxation that has been previously reported at lower carrier densities. We further observe a dynamic circular dichroism that arises from a photoinduced polarization in the exciton distribution between total angular momentum states. Our findings provide fundamental and application relevant insights into the spin-dependent exciton-exciton interactions in layered hybrid perovskites.
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