廣角入射X光波導管之垂直波導效應以及多片X光共振腔之研究

Beam compression in wide-angle incident x-ray waveguides and resonance in multiplate x-ray cavities

武柏瑋(Po-Wei Wu)

指導教授 ： 張石麟

國立清華大學/理學院/物理學系/碩士(2006年)

摘要

本論文分為兩個部份。

論文的第一部分是研究廣角入射波導管。以往的X光波導管都是讓X光由小角度入射或是由前方入射的方式進入波導管。我們試圖利用大角度入射的方式,讓由(113)原子面產生表面繞射光。樣品是將矽晶圓蝕刻出長2公分,高150μm,寬 5~100μm的波導管,然後在波導管的外面鍍上金,利用全反射讓表面繞射光在波導管中行進。由g1td掃描可以觀察到波導的現象,配合2theta掃描分析波導現象隨能量變化的結果。

論文的第二部份是模擬多片X光共振腔。在實驗上已經能成功觀察到共振干涉的現象,我們希望能用模擬在不同晶體片數的共振腔下,能量掃描的圖形會有什麼改變。由動力繞射理論的結果,經過Yuri程式的計算後得到不同能量下的穿透率,假設入射光為一高斯波包,找出能量掃描後的結果作傅立葉轉換的結果的意義，不同晶體片數之間的比,
以及多片時改變gap寬度的影響。

關鍵字

X光波導管 ； X光共振腔

並列摘要

This thesis dealt with two research topics, one relating to x-ray waveguides, the other to multiplate x-ray cavities.

For the former a given incident x-ray beam is usually coupled into a waveguide from the side or from the front at grazing or normal incidence condition. In contrast, here we propose to use surface diffraction beam of (1 1 3) reflection to guide x-rays in a wide angle incidence geometry. Waveguides of 150 μm in height, 2 cm in length and the width ranging from 5 to 100 μm were prepared from a 4-inch Si(001) crystal wafer by using the microelectronic lithography process, then plated with gold by thermal evaporation.Much more beams were collected in the waveguide
because of total reflection.

Second part is concerned with simulation of resonance in multiplate x-ray cavities. We have experimentally observed cavity resonance fringes in the Fabry-Perot resonators for hard x-rays, but at the same time try to simulate energy scans of cavities with different numbers of plates according to the x-ray dynamical theory, while energy spread of the incident beam is notionally gaussian distribution. We attempted to find out the meaning of Fourier transform, comparison between different numbers of plates, and effects on changing gap width of multiplate cavities.

並列關鍵字

X-ray waveguide ； X-ray cavity

參考文獻

[1] N. W. Ashcroft and N. D. Mermin, ”Solid State Physics”,

(Harcourt, Orlando, 1976), p. 101

(Springer, Berlin, 1984)

[4] D. Marcuse, ”Thoery of Dielectric Optical Waveguides”,

[5] Y. P. Feng et. al, Phys. Rev. Lett., 71, 537-540 (1993)