[(Ge_(5))Fe]_(∞)/四元环二嵌段共聚小分子/[(Ge_(5))Fe]_(∞)分子结自旋输运性质  

Spin transport through[(Ge_(5))Fe]_(∞)/4-membered ring-diblock molecules/[(Ge_(5))Fe]_(∞)junctions

作　　者：王欢 律海朝 张强[1] 刘晓杰 尹海涛 WANG Huan;Lü Hai-Chao;ZHANG Qiang;LIU Xiao-Jie;YIN Hai-Tao(Key Laboratory for Photonic and Electronic Bandgap Materials of Ministry of Education,School of Physics and Electronic Engineering,Harbin Normal University,Harbin 150025,China;College of Science,Qiqihar University,Qiqihar 161006,China)

机构地区：[1]哈尔滨师范大学物理与电子工程学院光电带隙材料教育部省部共建重点实验室,哈尔滨150025 [2]齐齐哈尔大学理学院,齐齐哈尔161006

出　　处：《原子与分子物理学报》2023年第1期31-36,共6页Journal of Atomic and Molecular Physics

基　　金：黑龙江省自然基金(LH2020A013)。

摘　　要：采用密度泛函理论和非平衡格林函数相结合的计算方法,研究四元环二嵌段共聚小分子自旋输运性质以及嵌入嘧啶基对分子结输运性质的影响.研究发现中心区为4,4′-二苯基联苯分子时,在极小偏压,磁阻接近于无穷大,随着偏压的增大磁阻逐渐减小,在较大偏压下磁阻变为负值.当嵌入嘧啶基后,在一定的偏压下,嵌入2个嘧啶基的分子结磁阻接近零,嵌入3个嘧啶基结构,磁阻小于零,嵌入4个嘧啶基结构时,磁阻最大.通过分析五种分子结在非平衡态下的透射谱,进一步对这些特性进行分析.Using first-principles calculations based on density functional theory combined with the non-equilibrium Green’s function formalism,we studied the spin transport properties of 4-membered ring-diblock molecules connecting two ferromagnetic polymer electrodes[(Ge)Fe],as well as the influence of embedded pyrimidine on transport properties of molecular junctions.It was found that when central region is 4,4′-Diphenylbiphenyl molecule,the magnetoresistance(MR)of the molecular junction approaches infinity at very small bias,and gradually decreases as the bias voltage increases and even decreases to a negative value under a large bias voltage.When two pyrimidines are embedded,the MR of the molecular junction is close to zero.For embedding three pyrimidines structure,MR value is less than zero.When four pyrimidines are embedded,the MR value of the system is the largest.By analyzing the transmission spectrum of the five kinds of molecular junctions in the non-equilibrium state,these characteristics were explained further.

关 键 词：分子结 自旋输运 磁阻 透射系数 

分 类 号：O441.6[理学—电磁学]