摘要
Single crystals of organic semiconductors with perfect crystal structure and minimal density of defects can exhibit high mobility and low spin scattering compared with their amorphous or polycrystalline counterparts.Therefore,these materials are promising candidates as the spin transport media to obtain long spin relaxation times and spin diffusion lengths in spintronic devices.However,the investigation of spin injection and transport properties in organic single crystals is hindered by the inability to construct devices such as single-crystalline organic spin valves(OSVs).Herein,thin and large organic single crystals of 6,13-bis(triisopropylsilylethynyl)pentacene(TIPS-pentacene)were grown on a liquid substrate and transferred to a target substrate carrying ferromagnetic electrodes to construct single-crystalline OSVs.The magnetoresistance(MR)responses of the single crystals were investigated to study their spin injection and transport properties.MR value as high as 17%was probed with an intermediate layer thickness of 269 nm.More importantly,spin transport was still observed in a single crystal of a thickness up to 457 nm,which was much larger than that of polycrystalline thin film.Our research provides a general methodology for constructing single-crystalline OSVs and paves the way to probe the intrinsic spin transport properties of organic semiconductors based on single crystals.
与非晶或多晶相比,有机半导体单晶具有完美的晶体结构和较少的结构缺陷,因而具有高迁移率和低自旋散射,使其有望在自旋电子器件中获得长自旋弛豫时间和长自旋扩散长度.然而,目前缺乏构筑单晶有机自旋阀(OSVs)的方法,阻碍了单晶有机半导体的自旋注入和输运特性的研究.针对这一挑战,本文提出了在液态衬底表面生长大面积薄层有机单晶,并转移至带有磁性电极的衬底以构筑有机单晶自旋阀的策略.我们成功探测到了TIPS-pentacene有机单晶在不同温度和不同厚度下的磁电阻响应,获得了高达17%的磁阻.更重要的是,在厚达457 nm的单晶中仍然可以观察到自旋输运,比多晶薄膜的自旋输运长度大得多.据我们所知,本研究是第一例工作的垂直结构有机单晶自旋阀.本研究为构建单晶OSV提供了一种通用的方法,为基于单晶的有机半导体本征自旋输运特性的研究奠定了基础.
作者
Ying Wang
Jiarong Yao
Shuaishuai Ding
Siyu Guo
Dapeng Cui
Xinyue Wang
Shuyuan Yang
Lijuan Zhang
Xinzi Tian
Di Wu
Chao Jin
Rongjin Li
Wenping Hu
王颖;姚佳荣;丁帅帅;郭思宇;崔大鹏;王新月;杨书院;张利娟;田馨孜;吴镝;金朝;李荣金;胡文平(Tianjin Key Laboratory of Molecular Optoelectronic Sciences,Department of Chemistry,School of Science,Tianjin University and Collaborative Innovation Center of Chemical Science and Engineering,Tianjin 300072,China;National Laboratory of Solid State Microstructures,Department of Materials Science and Engineering and Jiangsu Key Laboratory for Artificial Functional Materials,Nanjing University,Nanjing 210093,China;Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology,Department of Physics,School of Science,Tianjin University,Tianjin 300072,China;Joint School of National University of Singapore and Tianjin University,International Campus of Tianjin University,Binhai New City,Fuzhou 350207,China)
基金
the National Natural Science Foundation of China(61674116,51873148,51633006,and 52003190)
the Ministry of Science and Technology of China(2016YFA0202302)
the Natural Science Foundation of Tianjin(18JC-YBJC18400)。
