Spatial mapping of chiral-induced spin selectivity in chiral perovskite via spin-Schottky junction

作者：Minghui Li, Zhongwei Chen, Xiting Lang, Junchuan Zhang, Yongjie Jiang, Hao Tian, Fang Ye, Xirui Liu, Yangyang Gou, Herui Xi, Wei Guo, Jichun Ye, Matthew C. Beard, Haipeng Lu, Chuanxiao Xiao · 发表于：National Science Review · 年份：2025 · DOI：10.1093/nsr/nwaf295 · 被引用次数：5 · 研究领域：Magnetic properties of thin films、Advanced Condensed Matter Physics、Physics of Superconductivity and Magnetism

Chiral halide perovskite (c-HP) semiconductors exhibit on average a large chiral-induced spin selectivity (CISS) effect. Nevertheless, the microscopic details of CISS and its integration in opto-spintronic constructs remain nascent. Reliable reporting of CISS performance characteristics represents a significant challenge in providing the necessary design rules. We show a Kelvin probe force microscopy (KPFM) method that can quantitatively evaluate and spatially map the chirality-dependent surface contact potential difference resulting from the formation of a spin-Schottky junction. We revealed inhomogeneity in the CISS response, where low-CISS regions in the c-HP films reduce the overall macroscopic average, likely serving as a key factor in optimizing macroscopic performance. We also observed that although c-HP films made from higher precursor concentrations lead to thicker films and higher carrier concentrations with subsequent larger barrier heights in the Schottky junction, stronger spin relaxation due to non-ideal film quality reduces spin polarization.