Electron Spin Decoherence Dynamics in Magnetic Manganese Hybrid Organic–Inorganic Crystals: The Effect of Lattice Dimensionality
Haining Zheng, Arup Ghosh, M. J. Swamynadhan, Gang Wang, Qihan Zhang, Xiao Wu, Ibrahim Abdelwahab, Walter P. D. Wong, Qing-Hua Xu, Saurabh Ghosh, Jingsheng Chen, Branton J. Campbell, Alessandro Stroppa*, Junhao Lin*, Ramanathan Mahendiran*, and Kian Ping Loh*
Abstract：
Organic–inorganic metal hybrids with their tailorable lattice dimensionality and intrinsic spin-splitting properties are interesting material platforms for spintronic applications. While the spin decoherence process is extensively studied in lead- and tin-based hybrids, these systems generally show short spin decoherence lifetimes, and their correlation with the lattice framework is still not well-understood. Herein, we synthesized magnetic manganese hybrid single crystals of (4-fluorobenzylamine)2MnCl4, ((R)-3-fluoropyrrolidinium)MnCl3, and (pyrrolidinium)2MnCl4, which represent a change in lattice dimensionality from 2D and 1D to 0D, and studied their spin decoherence processes using continuous-wave electron spin resonance spectroscopy. All manganese hybrids exhibit nanosecond-scale spin decoherence time τ2 dominated by the symmetry-directed spin exchange interaction strengths of Mn2+–Mn2+ pairs, which is much longer than lead- and tin-based metal hybrids. In contrast to the similar temperature variation laws of τ2 in 2D and 0D structures, which first increase and gradually drop afterward, the 1D structure presents a monotonous rise of τ2 with the temperatures, indicating the strong correlation of spin decoherence with the lattice rigidity of the inorganic framework. This is also rationalized on the basis that the spin decoherence is governed by the competitive contributions from motional narrowing (prolonging the τ2) and electron–phonon coupling interaction (shortening the τ2), both of which are thermally activated, with the difference that the former is more pronounced in rigid crystalline lattices.
论文链接：
https://doi.org/10.1021/jacs.3c05503
媒体报道：
【材料】NUS罗健平团队JACS：锰系钙钛矿卤化物的晶格维度对电子自旋弛豫的影响
Ferroelectric Modulation in Flexible Lead-Free Perovskite Schottky Direct-Current Nanogenerator for Capsule-Like Magnetic Suspension Sensor
Feng Jiang, Gurunathan Thangavel, Xinran Zhou, Gupta Adit, Hongbo Fu, Jian Lv, Liuxiang Zhan, Yihui Zhang, Pooi See Lee*
Abstract：
The tribovoltaic nanogenerator (TVNG), a promising semiconductor energy technology, displays outstanding advantages such as low matching impedance and continuous direct-current output. However, the lack of controllable and stable performance modulation strategies is still a major bottleneck that impedes further practical applications of TVNG. Herein, by leveraging the ferroelectricity-enhanced mechanism and the control of interfacial energy band bending, a lead-free perovskite-based (3,3-difluorocyclobutylammonium)2CuCl4 ((DF-CBA)2CuCl4)/Al Schottky junction TVNG is constructed. The multiaxial ferroelectricity of (DF-CBA)2CuCl4 enables an excellent surface charge modulating capacity, realizing a high work function regulation of ≈0.7 eV and over 15-fold current regulation (from 6 to 93 µA) via an electrical poling control. The controllable electrical poling leads to elevated work function difference between the Al electrode and (DF-CBA)2CuCl4 compared to traditional semiconductors and halide perovskites, which creates a stronger built-in electric field at the Schottky interface to enhance the electrical output. This TVNG device exhibits outstanding flexibility and long-term stability (>20 000 cycles) that can endure extreme mechanical deformations, and can also be used in a capsule-like magnetic suspension device capable of detecting vibration and weights of different objects as well as harvesting energy from human motions and water waves.
论文链接：
https://doi.org/10.1002/adma.202302815
校友信息：
π-Lab 2020届硕士毕业生
郑海宁
毕业去向：PhD student 博士生
National University of Singapore
新加坡国立大学
Prof. Loh Kian Ping 组
研究方向：multiferroic perovskit 多铁钙钛矿
π-Lab 2020届硕士毕业生
蒋枫
毕业去向：PhD student 博士生
Nanyang Technological University
南洋理工大学
Lee Pooi See 组
研究方向：flexible electronics, nanogenerators 柔性电子学，纳米发电机
媒体报道：
又甜又硬核！一个月两篇SCI，影响因子均大于10，厦大这对情侣学霸把科研当情话！
编 辑：苑子恒 夏钟升
