中科院福建物质结构刘希涛团队报道了非手性层状钙钛矿混合铁电晶体圆偏振光检测的鲁棒自旋相关各向异性。相关研究成果发表在2022年8月1日出版的国际知名学术期刊《美国化学会杂志》。

圆偏振光（CPL）检测因其广泛的光电子和自旋电子学应用而引起了广泛的研究兴趣。铁电材料，特别是新兴的层状钙钛矿杂化铁电体，表现出显著的体光伏效应（BPVE），通过独特的工作概念为复数检测提供了重要的可能性。

该文中，研究人员首次证明了在一种新的层状混合钙钛矿铁电晶体（CPA）2FAPb2Br7（1，CPA是氯丙基氨，FA是甲脒）中实现稳定的角各向异性，该晶体在光学活性非手性极性点群中结晶。得益于显著的自发极化（5.1μC/cm²）和优良的半导体特性，1的单晶在光照下表现出显著的BPVE，具有高电流开/关开关比（约10³）。更有趣的是，由光学活性铁电体中自旋相关BPVE产生的角载流子漂移驱动，1显示出高度敏感的自供电复数检测性能，显示出高达0.98的鲁棒角各向异性因子，远高于通过材料固有手性实现的角各向异性系数。

该项工作为实现高灵敏度复数检测提供了前所未有的方法，为进一步设计用于手征光子应用的光学活性铁电体提供了依据。

附：英文原文

Title: Robust Spin-Dependent Anisotropy of Circularly Polarized Light Detection from Achiral Layered Hybrid Perovskite Ferroelectric Crystals

Author: Xiaoqi Li, Fafa Wu, Yunpeng Yao, Wentao Wu, Chengmin Ji, Lina Li, Zhihua Sun, Junhua Luo, Xitao Liu

Issue&Volume: August 1, 2022

Abstract: Circularly polarized light (CPL) detection has sparked overwhelming research interest for its widespread chiroptoelectronic and spintronic applications. Ferroelectric materials, especially emerging layered hybrid perovskite ferroelectrics, exhibiting striking bulk photovoltaic effect (BPVE) present significant possibilities for CPL detection by a distinctive working concept. Herein, for the first time, we demonstrate the realization of robust angular anisotropy of CPL detection in a new layered hybrid perovskite ferroelectric crystal (CPA)2FAPb2Br7 (1, CPA is chloropropylammonium, FA is formamidinium), which crystallized in an optically active achiral polar point group. Benefiting from the notable spontaneous polarization (5.1 μC/cm2) and excellent semiconducting characteristics, single crystals of 1 exhibit remarkable BPVE under light illumination, with a high current on/off switching ratio (ca. 103). More intriguingly, driven by the angular carrier drift originating from spin-dependent BPVE in optically active ferroelectrics, 1 displays highly sensitive self-powered CPL detection performance, showing a robust angular anisotropy factor up to 0.98, which is far more than those achieved by material intrinsic chirality. This work provides an unprecedented approach for realizing highly sensitive CPL detection, which sheds light on the further design of optically active ferroelectrics for chiral photonic applications.

DOI: 10.1021/jacs.2c06048

Source: https://pubs.acs.org/doi/10.1021/jacs.2c06048