Tunable and Large Magneto‐Photoluminescence for Single‐Crystalline Chiral Perovskites

Abstract Chiral lead halide perovskites (LHPs) possess natural optical activities (NOA), which are determined by the chirality‐induced spin–orbit coupling (SOC). This makes them potentially useful for chiroptical spintronic applications. Here, the effective manipulation of magneto‐photoluminescence (magneto‐PL) by circularly polarized light for chiral LHP single crystals, such as (R‐MBA)₂PbI₄ and (S‐MBA)₂PbI₄, is demonstrated. A large and negative magneto‐PL effect with a magnitude of 7% can be detected at the field strengths of ±900 mT at 4 K. The change of the magneto‐PL that is due to the left and right photoexcitation of circularly polarized light (σ ⁺ and σ ⁻) can reach 37.3%. Such an effect can be well elucidated by the recently developed theoretical model based on a field‐induced population difference at exciton states. It is found that the Landé g‐factors of photogenerated paramagnetic species and electron–hole pair lifetimes (τ) obey circular dichroism (CD). The results indicate that chirality can be indelibly imprinted on the photogenerated species. The work paves the way for the light and field manipulation of large magneto‐PL for the chiral LHPs in applications of chiroptical spintronics.