摘要(英) |
In nanoparticles are fabricated by employing thermal evaporation method and subsequently oxidized in air at a temperature under various oxidation times. XRD is utilized to determine the mean particle diameter (12.5 nm) of the In nanoparticles as grown. The composition of In/In2O3 is analyzed by refining the X-ray diffraction pattern using General Structural Analysis System (GSAS) program. In our study,the superconducting diamagnetic screening effect was measured through AC magnetic susceptibility (〖 χ〗^’=χ^’+iχ^’’).The temperature dependence of in-phase component χ^’ (T) can be described by the Scalapino’s expression,which allows extracting the superconducting transition temperature.There is an unconventional enhancement of critical (Tc) in the sample after oxidation.
The spin polarization effects are seen in M(H) curve which can be described by Langevin function,after fitting,we can get magnetic moment and saturated magnetization.The magnetic moment can be explained by thermal-induced effect.The saturated magnetization can be described by spin-wave excitation model.
After that,using GSAS to obtain In and In2O3 mass ratio,and saturated magnetization from Langevin function,we can figure out In and In2O3 magnetization.We found that the thermal-induced effect of In2O3 is more remarkable than In. |
參考文獻 |
[1] 吳豐宇, In/In2O3的超導奈米顆粒聚合體的超導性質探討,國立中央大學碩士論文(2009)
[2] C.Kittel,Introduction to Solid State Physics 8th edition,ISBN 978-0-471-41526-8
[3] 王進威,擬合X光繞射峰形判定奈米微粒粉末的粒徑分析,中央大學碩士論文(2006)
[4] A.C.Larson and R.B.Von Dreele,General Structure Analysis System (GSAS),Los Alamos National Labaratory Report LAUR 86-748(2004)
[5]張裕恆,李玉芝,超導物理,儒林圖書公司(1997)
[6]何鈞考,錫奈米微粒的超導參數與自旋極化,中央大學碩士論文(2006) [7]B.Muhlschlegel,D.J.Scalapino,R.Denton,phys.Rev.B6,5
(1972)
[8] W.-H. Li, C. C. Yamg, F. C. Tsao, S. Y. Wu, P.J. Huang, M. K. Chung and Y. D. Tao, Phys. Rev. B, 72, 214516 (2005)
[9] S.Morup and B.R.Hansen, Physical Review B 72, 024418 (2005). |