English  |  正體中文  |  简体中文  |  Items with full text/Total items : 67783/67783 (100%)
Visitors : 23129939      Online Users : 122
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Tips:
  • please add "double quotation mark" for query phrases to get precise results
  • please goto advance search for comprehansive author search
  • Adv. Search
    HomeLoginUploadHelpAboutAdminister Goto mobile version

    Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/80714

    Title: Effect of contact geometry on the spin transfer calculation in amine-ended single-molecule magnetic junctions
    Authors: 江冠融;CHIANG, KUAN-RONG
    Contributors: 物理學系
    Keywords: 單分子磁性接面;第一原理計算;非平衡格林函數;密度泛函理論;電子自旋傳輸;Single-molecule magnetic junction;First-principles calculation;Non-equilibrium Green′s function;Density Functional Theory;Spin transport
    Date: 2019-08-20
    Issue Date: 2019-09-03 15:01:00 (UTC+8)
    Publisher: 國立中央大學
    Abstract: 由於化學分子的多變性與在資料儲存、磁性感測器上應用的潛力,有機分子磁性接面在近期開始受到大量的關注。磁性材料與有機分子介面化學鍵結與交互作用不僅導致不同的自旋介面效應並明顯影響電子自旋傳輸行為,近期的研究也指出「鈷/對苯二胺/鈷」單分子磁性接面在拉伸下擁有極佳的自旋入射比率與異常磁阻效應。
    ;Organic-based magnetic junctions have attracted intensive attentions due to their diversity of molecular synthesis and potential applications on data storage and magnetic sensor. The so-called spinterface between ferromagnetic and organic molecules provides rich physics to closely correlate interfacial chemical bonding with spin transport properties. Recently, amine-ended single-molecule magnetic junction has been proposed with superior spin injection and anomalous magnetoresistance (MR) effect under stretching process.
    Since the exact contact geometries remains unknown but may play quite a crucial role in spinterface coupling, various contact geometries such as contact site, linker hydrogen ion dissociation and different central molecule are all considered in this study through the employment of density functional theory (DFT) with non-equilibrium green’s function (NEGF). On the basis of π-resonance channel in Co/BDA/Co junction, we propose Co/p-Terphenyl, 4,4′′-diamine (TBDA)/Co and Co/Proflavine/Co two highly spin-polarized amine-ended magnetic junctions with 132% and 248% MR ratio respectively under zero bias, which expected to be highly enhanced while applying source-drain bias voltage. On the other hand, amazingly, the dissociation of H ion at N linker results in an overwhelmingly change of spin-polarized channel at central molecule by controlling number of unpaired electron for N ion interacting with Co apex under different contact cites. These intriguing results may open up a new arena to engineer the spinterface between FM metal and organic molecule for desired magnetotransport properties and MR effect via the variety of choices in anchoring groups and contact geometries.
    Appears in Collections:[物理研究所] 博碩士論文

    Files in This Item:

    File Description SizeFormat

    All items in NCUIR are protected by copyright, with all rights reserved.

    社群 sharing

    ::: Copyright National Central University. | 國立中央大學圖書館版權所有 | 收藏本站 | 設為首頁 | 最佳瀏覽畫面: 1024*768 | 建站日期:8-24-2009 :::
    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback  - 隱私權政策聲明