English  |  正體中文  |  简体中文  |  Items with full text/Total items : 26994/38795
Visitors : 2392248      Online Users : 71
RC Version 4.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Adv. Search
LoginUploadHelpAboutAdminister

Please use this identifier to cite or link to this item: http://ntour.ntou.edu.tw:8080/ir/handle/987654321/17847

Title: 二氧化鈦、方解石、和摻鉻釩酸釔晶體之兆赫波段光學常數
Terahertz optical constant measurements of Titanium Dioxide,Calcite, and Cr-doped Yttrium Orthovanadate crystals.
Authors: Jia-Hao Wang
王家豪
Contributors: NTOU:Institute of Optoelectronic Sciences
國立臺灣海洋大學:光電科學研究所
Keywords: 兆赫波光學常數;二氧化鈦;方解石;摻鉻釩酸釔;摻鉻鈣釩酸釔;謝米爾方程式
Terahertz optical constant;TiO2;Calcite;Cr-YVO4;CrCa-YVO4;Sellmeier equation
Date: 2010
Issue Date: 2011-07-04
Abstract: 本研究是利用兆赫波光譜技術量測二氧化鈦(TiO2)、方解石(Calcite)以及摻鉻釩酸釔(Cr-YVO4)和摻鉻鈣釩酸釔(CrCa-YVO4)四個雙折射晶體在兆赫波波段下的光學常數,藉此討論實驗樣品的雙折射大小和吸收。在0.2THz~1.0THz範圍,得到二氧化鈦晶體的雙折射大小為3.61~3.65,其次是摻鉻釩酸釔之雙折射大小為0.972~1.002以及摻鉻鈣釩酸釔之雙折射大小為0.962~0.984,方解石之雙折射大小為0.13~0.05。將量測到的實部折射率結果,使用謝米爾方程式(Sellmeier Equation)來擬合折射率趨勢,找出在遠紅外波段的共振吸收頻率 以及在低頻時的相對介電常數 和參考文獻做比較結果是相符的。最後,利用實驗樣品的雙折射特性來討論在1THz( λ=300um )時達成四分之一波板所對應的厚度,分別得到二氧化鈦在厚度為0.02mm時和摻鉻釩酸釔在厚度為0.075mm以及摻鉻鈣釩酸釔在厚度為0.076mm時可達成四分之一波板的條件,但對於方解石而言,在此波段由於雙折射大小有明顯變化且下降,因此並不適合作為四分之一波板的材料。
In this work, we measure the terahertz optical constants of TiO2, Calcite, Cr-YVO4, and CrCa-YVO4 by terahertz time domain spectroscopy. In the range of 0.2~1.0THz, we can get the birefrigence properties as below:△n=3.61~3.65 for TiO2, △n=0.972~1.002 for Cr-YVO4, △n=0.962~0.984 for CrCa-YVO4, △n=0.13~0.05 for Calcite. The measured real refractive indices were fitted using a Sellmeier equation. The results show that the Sellmeier equation fits well with the data throughout the frequency range and imply the absorption wavelengths in the far-infrared frequency. From the Sellmeier coefficients, we compare the dielectric constant in the low frequency with literatures and the result is good. Finally, we use the birefringence properties to design quarter-wave plates for a 0.02mm thick piece of TiO2 and for a 0.075mm thick piece of Cr-YVO4 and for a 0.076mm thick piece of CrCa-YVO4, and Calcite is unable to make a quarter-wave plate because the birefringence property is too small in the range of 0.2~1.0THz.
URI: http://ethesys.lib.ntou.edu.tw/cdrfb3/record/#G0M97880021
http://ntour.ntou.edu.tw/ir/handle/987654321/17847
Appears in Collections:[光電科學研究所] 博碩士論文

Files in This Item:

File Description SizeFormat
index.html0KbHTML279View/Open


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

 


著作權政策宣告: 本網站之內容為國立臺灣海洋大學所收錄之機構典藏,無償提供學術研究與公眾教育等公益性使用,請合理使用本網站之內容,以尊重著作權人之權益。
網站維護: 海大圖資處 圖書系統組
DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback