Exploring how hydrogen at gold-sulfur interface affects spin transport in single-molecule junction  

作　　者：Jing Zeng Ke-Qiu Chen Yanhong Zhou 曾晶;陈克求;周艳红(College of Physics and Electronic Engineering,Hengyang Normal University,Hengyang 421002,China;Department of Applied Physics,School of Physics and Electronics,Hunan University,Changsha 410082,China;Hunan Provincial Key Laboratory of Intelligent Information Processing and Application,Hengyang 421002,China;College of Science,East China Jiao Tong University,Nanchang 330013,China)

机构地区：[1]College of Physics and Electronic Engineering,Hengyang Normal University,Hengyang 421002,China [2]Department of Applied Physics,School of Physics and Electronics,Hunan University,Changsha 410082,China [3]Hunan Provincial Key Laboratory of Intelligent Information Processing and Application,Hengyang 421002,China [4]College of Science,East China Jiao Tong University,Nanchang 330013,China

出　　处：《Chinese Physics B》2020年第8期525-530,共6页中国物理B（英文版）

基　　金：the National Natural Science Foundation of China(Grant Nos.11674092,11804093,and 61764005);the Natural Science Foundation of Hunan Province,China(Grant No.2019JJ40006);the Scientific Research Fund of the Education Department of Hunan Province,China(Grant No.18B368);the Science and Technology Development Plan Project of Hengyang City,China(Grant No.2018KJ121);the Science and Technology Plan Project of Hunan Province,China(Grant No.2016TP1020).

摘　　要：Very recently,experimental evidence showed that the hydrogen is retained in dithiol-terminated single-molecule junction under the widely adopted preparation conditions,which is in contrast to the accepted view[Nat.Chem.11351(2019)].However,the hydrogen is generally assumed to be lost in the previous physical models of single-molecule junctions.Whether the retention of the hydrogen at the gold-sulfur interface exerts a significant effect on the theoretical prediction of spin transport properties is an open question.Therefore,here in this paper we carry out a comparative study of spin transport in M-tetraphenylporphyrin-based(M=V,Cr,Mn,Fe,and Co;M-TPP)single-molecule junction through Au-SR and Au-S(H)R bondings.The results show that the hydrogen at the gold-sulfur interface may dramatically affect the spin-filtering efficiency of M-TPP-based single-molecule junction,depending on the type of transition metal ions embedded into porphyrin ring.Moreover,we find that for the Co-TPP-based molecular junction,the hydrogen at the gold-sulfur interface has no obvious effect on transmission at the Fermi level,but it has a significant effect on the spin-dependent transmission dip induced by the quantum interference on the occupied side.Thus the fate of hydrogen should be concerned in the physical model according to the actual preparation condition,which is important for our fundamental understanding of spin transport in the single-molecule junctions.Our work also provides guidance in how to experimentally identify the nature of gold-sulfur interface in the single-molecule junction with spin-polarized transport.

关 键 词：transport properties molecular electronic devices gold-sulfur interface density-functional theory nonequilibrium Green’s functions 

分 类 号：O641.1[理学—物理化学] TN30[理学—化学]