溫度及壓力變化為探討物性的兩個重要的變因，本研究主要探討壓力與物性變化的關係，首先發展高壓比熱系統，主要利用鑽石高壓砧(Diamond anvil cell)結合熱弛豫法(Thermal relaxation method)，其優點為可量測樣品重量約5~10mg。本研究量測CeAl2在不同壓力下，其反鐵磁轉變溫度(TN)與壓力的關係，發現當壓力增加至4 kbar時，其TN從3.8 K增加至4.6 K。由於外加壓力使晶格產生些許變化，造成交換能改變而影響TN的變化。
將YBCO塊材製作成奈米微粒，使表面積效應造成樣品本身產生內壓力，造成晶格縮收達到加壓的效果。本研究利用準分子雷射濺鍍法製作奈米微粒，探討在零維的奈米尺度下，超導性質的改變。本實驗得到3 nm、35 nm及70 nm不同大小的YBCO奈米微粒，發現其超導轉變溫度皆在91 K，但70 nm樣品的超導成分比例只剩1.5%，且隨著尺寸的縮小，超導比例也跟著減少，至5 nm時，超導比例只剩下0.25%。Hc1也是隨著尺寸縮小而減少，從70 nm的HC1 為450 Oe到5 nm的HC1 為170 Oe。YBCO相干長度大約為2 nm，在粒徑5 nm時仍大於相干長度2 nm，故還有少部份的超導存在。

In this thesis our main objectives are to study the correlation between pressure and physical properties of materials that show interesting behavior. Temperature and pressure are two variables we used in this study as they are important parameters to better understand material characteristics. A major accomplishment in this study is the development of a high pressure specific heat system that utilizes a Diamond anvil cell together with the thermal relaxation method so that we can study small sample in the order of milligram. Using this high pressure specific heat system, we observed that the Neel temperature of CeAl2 increases with increasing pressure.
It is known nanoparticle can generate relatively large internal strain due to the surface effect and may change its physical properties. It is thus interesting to find out how the YBCO superconductor behaves if it is in nanoparticle form. We have fabricated with nanoparticle YBCO using pulsed laser deposition method. We found that for YBCO nanoparticles of sizes: 5nm, 35nm, and 70nm, their superconducting transition temperature remain to be ~ 90 K, however, the superconducting volume fraction is much reduced. For 70nm particle the volume fraction is ~ 1.5%, and for 5 nm only 0.25%. The critical field Hcl also decreases with size from 450 Oe for 70 nm particle down to 170 Oe for 5 nm.

參考資料
【1】 黃怡禎，科學發展，358期，34頁(2002)
【2】 S. Raymond and D. Jaccard, Phys. Rev. B, 61,p8679 (2000)
【3】C. M. Lin, T. L. Hung, Y. H. Huang, K. T. Wu, M. T. Tang, C. H. Lee, C. T. Chen and Y. Y. Chen, Phys. Rev. B, 75,p125426 (2007)
【4】羅吉宗、戴明鳳、林鴻明等編著，奈米科技導論，p2-19(2003)
【5】何建民，低溫．超導．磁浮，p39-48，(1996)
【6】Michael Tinkham，Introduction of superconductivity，p10-12，(1996)
【7】林坤閱，二鋁化鈰奈米微粒的重費米行為，輔大碩士論文，p2-4，(1998)
【8】C. Kittel，Introduction of solid state physics，p107-156，(2004)
【9】S. Chikazumi，張煦、李學養合譯，磁性物理學，p6-14 (1990)
【10】C. Y. Ho and A. Cezairliyan，Specific heat of solids，p34-60 (1988)
【11】陳呈芳，熱力學概論，全華出版社，p133-143 (1993)
【12】張裕恆、李玉芝，超導物理，p321-351 (1990)
【13】汪建民，材料分析，中國材料科學學會，p175-235，(1998)
【14】楊鴻昌，最敏感的感測元件SQUID及其前瞻性應用，物理雙月刊，二十四卷五期，p652，(2002)
【15】呂助增，固態電子學，國立編譯館，p350-353，(1996)
【16】岳志霖，五種砷鹽酸類礦物之高壓拉曼研究，成大碩士論文，p10-16，(1995)
【17】J. F. Lin, J. Shu, H. K. Mao and R. J. Hemley，Review of Scientific Intruments，74，p4732 (2003)
【18】余樹楨，晶體之結構與性質，國立編譯館，p238-455，(2003)
【19】H.K Mo, J. Xu and P. M. Bell，Journal of Geophysical research，91，p4673，(1986)
【20】林志明，超高壓技術簡介-應用於半導體相變研究，物理雙月刊，二十卷五期，p600 (1998)
【21】吳聲嵩，硒化鎘鋅磊晶層之高壓拉曼散射光譜研究，交大碩士論文，p13 (1995)
【22】謝雲生，拉曼光譜簡介，物理雙月刊，七期一卷，p25 (1985)
【23】H.K Mo, J. Xu and P. M. Bell，Journal of Geophysical research，91，p4673，(1986)
【24】A.Berton, J. Chaussy, G. Chouteau, B. Cornut, J. Peyrard and R. Tournier，J. Phys. C5，40，471(1979)
【25】E. Hanke and A. Eichler，High Pressure Research，3，p180，(1990)
【26】A. Eichler, E. Hanke and J. Michal，Physica B，194-196，p183，(1994)
【27】J. Zhang, Y. Cui, D. Deng, X. Li and G. Cheng，Physics Letters A，263，p452，(1999)
【28】E. Morosan, H. W. Zandbergen, B. S. Dennis, J. W. G. Bos, et. al，Nature PHysics ，2，p544，(2006)
【29】Derek J. Long，the Raman Effect: A unified treatment of Raman scattering by molecules，Wiley & Sons，p48，(2002)