Rapid spin depolarization in the layered 2D Ruddlesden Popper perovskite (BA)(MA)PbI

Michael Kempf; Philipp Moser; Maximilian Tomoscheit; Julian Schröer; Jean-Christophe Blancon; Rico Schwartz; Swarup Deb; Aditya Mohite; Andreas V. Stier; Jonathan J. Finley; Tobias Korn

doi:10.1021/acsnano.3c09001

arXiv · 2309.09784

Rapid spin depolarization in the layered 2D Ruddlesden Popper perovskite (BA)(MA)PbI

Michael Kempf·Philipp Moser·Maximilian Tomoscheit·Julian Schröer·Jean-Christophe Blancon·Rico Schwartz·Swarup Deb·Aditya Mohite·Andreas V. Stier·Jonathan J. Finley·Tobias Korn

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Abstract

We report temperature-dependent spectroscopy on the layered (n=4) two-dimensional (2D) Ruddlesden-Popper perovskite (BA)(MA)PbI. Helicity-resolved steady-state photoluminescence (PL) reveals no optical degree of polarization. Time-resolved PL shows a photocarrier lifetime on the order of nanoseconds. From simultaneaously recorded time-resolved differential reflectivity (TR$\Delta$R) and time-resolved Kerr ellipticity (TRKE), a photocarrier lifetime of a few nanoseconds and a spin dephasing time on the order of picoseconds was found. This stark contrast in lifetimes clearly explains the lack of spin polarization in steady-state PL. While we observe clear temperature-dependent effects on the PL dynamics that can be related to structural dynamics, the spin dephasing is nearly T-independent. Our results highlight that spin dephasing in 2D (BA)(MA)PbI occurs at time scales faster than the exciton recombination time, which poses a bottleneck for applications aimingto utilize this degree of freedom.

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Michael Kempf, Philipp Moser, Maximilian Tomoscheit, Julian Schröer, Jean-Christophe Blancon, Rico Schwartz, Swarup Deb, Aditya Mohite, Andreas V. Stier, Jonathan J. Finley, Tobias Korn. 2023-09-18. Rapid spin depolarization in the layered 2D Ruddlesden Popper perovskite (BA)(MA)PbI. https://doi.org/10.1021/acsnano.3c09001

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