Quantification of Chirality Induced Spin–Orbit Coupling for Long Spin Polarized Lifetime in Hybrid Perovskite

Long spin lifetimes are crucial for maintaining robust spin states during propagation in spintronic devices. Spin-orbit coupling (SOC) in chiral hybrid perovskites can induce chirality-dependent spin splitting, facilitating the manipulation of spin polarization. In this study, we introduce a chiral organic molecule, (<i>R</i>/<i>S</i>)-4-(aminoethyl)piperidinium (4AEP), into iodide-lead-based structures to synthesize chiral [(<i>R</i>/<i>S</i>)-4AEP]PbI₄ crystals and thin films. Using circularly polarized pump-probe techniques, we examine the carrier spin dynamics in [(<i>R</i>/<i>S</i>)-4AEP]PbI₄. Our results demonstrate that chirality-induced spin splitting significantly enhances the spin-polarization lifetime, achieving a spin splitting of approximately 130 meV at the valence band maximum and spin lifetimes exceeding 1 ns. Density functional theory (DFT) calculations reveal that opposite spin states exist in the <i>R</i>- and <i>S</i>-chiral samples with substantial spin splitting. These findings highlight the potential of chiral hybrid perovskites for spintronics applications.