本計劃將繼續發展奈米粉粒的製作技術,尋找有別於塊材的新穎物性。研究重點放在粒徑變小,表面低維度效應與量子侷域效應明顯後,所引發物理特性的改變,探討主軸在奈米粉末(nanopowder)與粉粒聚合體(nanocompact)的電傳輸、磁阻、磁性、與熱性質。我們採用熱蒸鍍法製作一系列粒徑各異的奈米微粒,也選擇性的混合多種奈米微粒再施以選定的機械壓力來製作粉粒聚合體。在奈米粉末基本物性研究方面,我們擬探討微粒間交互作用的行為,規劃的主題為(1)零維奈米超導顆粒間的交互作用對其超導特性的影響,探討超小超導系統裡麥斯樂(Meissner)效應、超導溫度、與臨界磁場因交互作用所引發的改變;(2)零維奈米磁性顆粒間的交互作用對其巨觀磁特性的影響,探討超小磁性系統裡磁相關長度、磁? 行為、與磁化強度因交互作用所引發的改變。在新穎奈米微粒聚合體材料開發與應用方面,則擬(1)利用調置奈米聚合體的電傳輸行為的方法,來尋找具實用性而有新穎功能的材料;(2)尋找具較大磁阻的奈米聚合體材料,以混合非磁性與磁性微粒來製造傳導電子在微粒間穿隧傳輸的機會,放大穿隧傳輸磁阻效應。 We propose to continue refining the fabrication processes for obtaining ultra smaller nanoparticles for various elements. In some cases, selective nanoparticles will be mixed thoroughly, followed by us ing a mechanical pressure to squeeze the nanoparticles into a compact form, and form nanocompacts. The basic properties of the nano-powders and nanocompacts will be studied by measuring resistivity, magnetoresistivity, magnetic susceptibility, and specific heat. Special attention will be paid on comparing the property changes caused by the reduction of the particle size, especially when the size reaches manometer scale. For nano-powders, the property changes resulted from the interactions among zero dimensional superconducting nanoparticles and among zero dimensional magnetic nanoparticles will be studied. For nanocompacts, we propose to search for new functional materials by tuning the transport behavior and for materials that having an appreciable magnetoresistive responses. 研究期間:9608 ~ 9707