(138c) Engineering Spin Dephasing in Metal-Halide Perovskite Nanomaterials for Quantum Information and Spintronics

Inorganic metal-halide perovskites have emerged as a promising platform for quantum information and spintronic applications, due to their large spin-orbit coupling, high photoluminescence quantum yields, photostability, and optical spin selection rules. Specifically, CsPbBr₃ nanocrystals also exhibit long optical coherence times and short photoluminescence lifetimes, initiating metal-halide perovskites as enticing single-photon emitters. For quantum information and spintronic devices, metal-halide perovskites materials also require long inhomogeneous spin-dephasing time (T₂*), for reliable initialization, transport, manipulation, and read out spins. However, to date, there have been no measurements of T₂* in CsPbBr₃ nanomaterials. Moreover, there is no understanding of how T₂* changes in different metal-halide perovskite morphologies relevant for spintronic applications. This lack of understanding prevents rational engineering of spin properties, limiting application of an exciting class of materials.

Here, we use time-resolved Faraday rotation to study the inhomogeneous spin dephasing dynamics in CsPbBr₃ nanostructures for the first time. Combining temperature and magnetic field dependent time-resolved Faraday rotation and photoluminescence, we describe a cohesive mechanism for spin dephasing in CsPbBr₃. Leveraging these results, we engineer photoluminescence lifetime limited T₂*. In addition, we explore how the spin dephasing properties change with different morphologies and structures relevant for devices. These measurements initiate metal-halide perovskite nanomaterials for spintronic and quantum-information applications and provide a roadmap for the future development of inorganic and hybrid metal-halide perovskites