“小分子机器”量子结构的构造及其物性  

The construction and structure-property manipulation of “small-molecule machines”

作　　者：张余洋[1,2] 杜世萱 高鸿钧[1,2] Yu-Yang Zhang;Shi-Xuan DU;Hong-Jun Gao(Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China)

机构地区：[1]中国科学院物理研究所北京100190 [2]中国科学院大学物理科学学院北京100049

出　　处：《科学通报》2018年第14期1255-1264,共10页Chinese Science Bulletin

基　　金：国家自然科学基金重大研究计划(61390501)、国家重点基础研究发展计划(2013CBA01600)、中国科学院先导培育专项(XDPB0601,XDPB08-1)和中国科学院率先行动“百人计划”资助

摘　　要：低维量子结构的构筑及调控是物理学向小尺度研究方向延伸的核心问题之一.本文重点围绕高鸿钧及合作者在"小分子机器"量子结构的构造及其物性方面开展的研究,系统地介绍了他们在单原子层次上设计、构造和调控的若干小分子机器量子结构.代表性工作有:(1)构筑了四叔丁基酞菁锌((t-Bu)4-Zn Pc)分子在Au(111)表面上"抛锚"的、带有固定偏心轴的单分子转子及其有序阵列,证实了转动行为的可调控性;(2)实现了单个小分子极限尺度(0.6 nm)的可逆电导转变,进而实现了稳定、重复、可逆的超高密度信息存储中的原理性应用;(3)首次直接证实代表性的"分子机器"轮烷(Rotaxane)分子的构型及其电导的可逆转变,澄清了当时化学界的一个争论热点,该热点也是2016年诺贝尔化学奖的主要成果;(4)通过单个H原子的吸脱附实现了酞菁锰(Mn Pc)分子在Au(111)表面Kondo效应的调控,这种单个自旋量子态的可逆控制,实现了极高密度信息存储(>40 TB/cm^2)的原理性应用;(5)在通过"原子手术"Mn Pc分子所创制的一种新"功能体系"上发现了朗德g因子在原子尺度上具有的空间分布不均匀性,这是长期以来一直未解决的问题.这些系统工作为单分子发电机/无线电辐射器及纳米电子器件等的构造组装与应用奠定了基础.Constructing low-dimensional quantum devices and manipulating their properties is one of the key research directions in physics.Due to their intrinsic structural diversities and ingenious functions as small building blocks,small molecules are a significant resource to build quantum machines for various applications,ranging from nano-rotors to ultrahigh-density information storage.The research in this project focuses on the design,construction,and structure-property manipulation of ＂small molecule machines＂ using scanning tunneling microscopy/spectroscopy（STM/STS）.The primary discoveries include the following：（1） We construct a large-scale,highly-ordered array of anchored,single-molecule rotors with well-defined axis on gold surfaces using tetra-tert-butyl zinc phthalocyanine（（t-Bu）4-Zn Pc） molecules.Experiments and theoretical calculations reveal the role of gold adatoms as the well-defined contact between the molecule and the surface.We further verified the manipulation of molecular rotors by putting the molecule at different regions of the surface and by changing the functional groups of the molecules.We also develop a new methodology to determine molecular configurations of a large molecular complex in a dynamical process on a metal surface by combining time-resolved tunneling spectroscopy（I-t spectra） and density functional theory calculations（DFT）.（2） We demonstrate a reversible conductance transition on the molecular scale（0.6 nm） in a complex of 3-nitrobenzal malononitrile and 1,4-phenylenediamine,by the application of local electric field pulses.Macroscopic and local current-voltage（I/V） measurements confirm an excellent electrical-bistability behavior.We also suggest that the conductance transition may arise from the disorder-to-crystalline transition in the thin film.（3） We investigate the structure and conductance of rotaxane molecules.For the first time,we reveal that the conductance switching in rotaxane-based devices is an inherent property of rotaxane m

关 键 词：小分子机器 纳米物理与器件 量子调控 分子马达 超高密度信息存储 

分 类 号：O413[理学—理论物理]