Mode locking of hole spin coherences in CsPb(Cl,Br)${}_3$ perovskite nanocrystals

Abstract

The spin physics of perovskite nanocrystals with confined electrons or holes is attracting increasing attention, both for fundamental studies and spintronic applications. Here, stable CsPb(Cl${}_{0.5}$Br${}_{0.5}$)${}_3$ lead halide perovskite nanocrystals embedded in a fluorophosphate glass matrix are studied by time-resolved optical spectroscopy to unravel the coherent spin dynamics of holes and their interaction with nuclear spins of the ${}^{207}$Pb isotope. We demonstrate the spin mode locking effect provided by the synchronization of the Larmor precession of single hole spins in each nanocrystal in the ensemble that are excited periodically by a laser in an external magnetic field. The mode locking is enhanced by nuclei-induced frequency focusing. An ensemble spin dephasing time $T_2^{\ast }$ of a nanosecond and a single hole spin coherence time of $T_2=13$ns are measured. The developed theoretical model accounting for the mode locking and nuclear focusing for randomly oriented nanocrystals with perovskite band structure describes the experimental data very well.

Main paper of 9 pages and 3 figures. Supplementary material of 16 pages and 12 figures

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Cited by in corpus (5)

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• Coherent Spin Dynamics of Electrons in Two-Dimensional (PEA)${}_2$PbI${}_4$ Perovskites
• Hole spin coherence in InAs/InAlGaAs self-assembled quantum dots emitting at telecom wavelengths
• Perovskite Nanocrystals as Emerging Single-Photon Emitters: Progress, Challenges, and Opportunities