English  |  正體中文  |  简体中文  |  Items with full text/Total items : 51258/86283 (59%)
Visitors : 8017242      Online Users : 62
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library & TKU 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://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/32568


    Title: 量子尺寸效應對鉭與鋁之超導性的影響
    Other Titles: Quantum size effect on the superconductivity of Ta and Al
    Authors: 彭翊凱;Peng, Yi-kai
    Contributors: 淡江大學物理學系碩士班
    張經霖;Chang, Ching-lin
    Keywords: 尺寸效應;超導;比熱;磁性;奈米微粒;size effect;Superconductivity;Specific heat;nanoparticle
    Date: 2005
    Issue Date: 2010-01-11 02:21:52 (UTC+8)
    Abstract: 本篇論文主要探討量子尺寸效應對鉭與鋁塊材和奈米微粒之超導性影響的研究,我們利用熱熔法製作鉭與鋁的塊材,利用準分子雷射製作鉭與鋁的奈米微粒樣品,再利用比熱儀與超導量子干涉磁量儀量測其比熱與磁化率等性質。一般塊材的鉭以立方體結構存在,此種結構的鉭稱為α-Ta,α-Ta為具超導性的超導體TC=4.48K,在鉭的奈米微粒研究中我們發現,樣品中除了原先的立方體結構外,也開始含有不具超導性的長方體結構(β-Ta),且隨著粒徑的縮小,β-Ta在樣品中的含量也開始增加。在比熱的量測中我們看到隨著粒徑的縮小,樣品能階的劈裂開始變大,當能階的劈裂大於超導的能隙時,樣品將不復有超導性,所以奈米微粒的樣品中,超導在比熱上造成的峰值變的微弱。在磁性的量測部分我們看到隨著粒徑的縮小,奈米微粒樣品的抗磁性變的越來越弱,並且開始有磁滯曲線的現象發生,磁滯曲線的發生是由樣品本身的特性或是雜質所造成的,需要再進一步的討論。
    在研究鋁的奈米微粒物性時,我們看到其超導溫度沒有太大的改變,但超導在比熱上所造成的峰值同樣隨著粒徑的縮小而變的微弱。
    The main purpose of this article is to study the properties of superconductivity about Al, Ta bulk and the nanoparticles and try to analyze the quantum size effect. We make Al and Ta bulk into nanoparticles by Excimer Laser. By studying specific heat and magnetic susceptibility, the correlations of superconductivity and magnetism with the size of Al and Ta were reported. In studying the physical properties for nanoparticles of Tantalum, the content of β-Ta which structure is tetragonal increases with particle size decrease. The superconductivity will no longer exist when the electronic energy level splitting is larger than the energy gap of superconductivity. So the suppression of superconductivity in nanoparticles may come from both the β-Ta which is not superconductive and the energy level spacing. That is why the superconductivity is more and more weak when the particles size decrease. In studying the physical properties for nanoparticles of aluminum, we can also see the superconductivity be suppressed by the energy level spacing.
    Appears in Collections:[物理學系暨研究所] 學位論文

    Files in This Item:

    File SizeFormat
    0KbUnknown167View/Open

    All items in 機構典藏 are protected by copyright, with all rights reserved.


    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library & TKU Library IR teams. Copyright ©   - Feedback