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一維光子晶體傳輸特性的研究畢業(yè)論文-免費閱讀

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【正文】 參考文獻(xiàn)[1] ,2009年第09期[2] ,2008年[3] ,2008年[4] ,2006年[5] ,第21卷第4期,2005年8月[6] :科學(xué)出版社,2006.[7] 劉平,羊紅光,第29卷第2期,2008年6月[8] ,2004年[9] 徐雙,第27卷第4期,2007年12月[10] (TMM),2002年[11] 周梅,陳效雙,季亞林,王少偉,,第22卷第3期,2003年6月[12] 羅朝明,孫軍強(qiáng),(自然科學(xué)版),第19卷第1期,2006年3月[13] 王身云,(工科版),第29卷第2期,2007年6月附錄附錄一:英文文獻(xiàn)Photonic Crystal FibersPhilip RussellStandard “step index” optical fibers guide light by total internal reflection, which operates only if the core has a higher refractive index than the encircling cladding.Rays of light in the core, striking the interface with the cladding, are pletely wave nature of light dictates that guidance occurs only at certain angles, ., that only a small number of discrete “modes” can form. If only one mode exists, the fiber is known as “single mode.”In 1991, the idea emerged that light could be trapped inside a hollow fiber core bycreating a periodic wavelengthscale lattice of microscopic holes in the cladding glass—a “photonic crystal” (1). To understand how this might work, consider that all wavelengthscale periodic structures exhibit ranges of angle and color (“stop bands”) where incident light is strongly reflected. This is the origin of the color in butterfly wings, peacock feathers, and holograms such as those found on credit cards. In photonic band gap (PBG) materials, however, these stop bands broadento block propagation in every direction, resulting in the suppression of all optical vibrationswithin the range of wavelengths spanned by the PBG (2). Appropriately designed,the holey photonic crystal cladding,running along the entire length of the fiber,can prevent the escape of light from a hollow core. Thus, it bees possible toescape the straitjacket of total internal reflection and trap light in a hollow fiber core surrounded by glass.In the early 1970s, there had been the suggestion that a cylindrical Bragg wave guide might be produced in which rings of high and lowrefractive index are arranged around a central core (3). Recently, a successful solidcore version of this structure, made using modified chemical vapor deposition(MCVD), was reported (4). The effort is now heading toward a hollowcore version,an ambitious goal that requires a materials system with much larger refractive index contrast than the few percent offered by MCVD (5).Was it realistic to imagine making a photonic crystal fiber (PCF)? Fiber fabricatorswho have long memories will recall how difficult it was to make “single material”fibers. Proposed in the 1970s as lowloss singlemode fibers and made entirely frompure silica, they consisted of a tubular cladding shell connected to a central core bythin webs of glass (6). However, such fibers proved very hard to make, and work onthem was abandoned with the advent of MCVD (7). Fig. 1. A stack of glass tubes and rods (a) is constructed as a macroscopic “preform” with the required photonic crystal structure. It is then fused together and drawn down to fiber (c) in two stages using a standard fiber drawing tower. To soften the silica glass, the furnace (b) runs at 1800176。入射光的偏振狀態(tài)不同,將形成不同的禁帶結(jié)構(gòu),這體現(xiàn)在禁帶中心位置及禁帶寬度的差異。而隨著N的增加,禁帶的透射率越來越接近于零,同時禁帶邊沿越來越抖,而禁帶的位置相對固定,幾乎不隨周期的增加而變化。從圖42(a)(c)中可以看出,隨著周期的增加,一維光子晶體的禁帶特征逐漸增強(qiáng),帶隙中的反射率越來越高,很明顯,禁帶寬度隨介質(zhì)層的光學(xué)厚度的增大基本上呈線性增加,這表明膜層厚度對禁帶寬度也有影響。在設(shè)計研究單位和工業(yè)部門,MATLAB被廣泛用于科學(xué)研究和解決各種具體問題。經(jīng)過多年的國際競爭,MATLAB 已經(jīng)占據(jù)了數(shù)值型軟件市場的主導(dǎo)地位。1983年春天,Cleve Moler到Stanford大學(xué)講學(xué),MATLAB深深地吸引了工程師John Little。絕大部分元素的計算都可在此界面操作。 and Jouanin。 Benisty, H.。而系統(tǒng)已設(shè)置了幾種默認(rèn)系統(tǒng)。對第N層介質(zhì),其左界面的場矢量為、右界面的場矢量為、則有: ()式中,是第N層介質(zhì)的傳輸特性矩陣。本節(jié)主要從電磁學(xué)的角度對一維光學(xué)傳輸特性矩陣進(jìn)行了推導(dǎo)。一束頻率為ω的光從左向右正入射(θ=0)。構(gòu)造量子阱結(jié)構(gòu)光子晶體和異質(zhì)結(jié)構(gòu)光子晶體,深入研究這兩種結(jié)構(gòu)光子品體的能帶特性。除了以上介紹的幾種方法,光子晶體的制作方法還有很多種,目前比較受關(guān)注的還有多光子聚合(主要是雙光子聚合)法和分子生物組裝法等等。Shoji等川八束HeCd(=442nm)激光連續(xù)照射感光樹脂,得到500m500m150m的光子晶體結(jié)構(gòu)。為了提高介電比,制備出合適的網(wǎng)絡(luò)拓?fù)浣Y(jié)構(gòu),發(fā)展了模板法,即以顆粒小球所構(gòu)成的緊密堆積結(jié)構(gòu)為模板,向小球間隙填充高介電常數(shù)的Si、Ge、TiO2等材料,然后通過鍛燒、化學(xué)腐蝕等方法將模板小球除去,得到三維多孔周期結(jié)構(gòu),這種結(jié)構(gòu)稱為反蛋白石結(jié)構(gòu)。單分散的聚苯乙烯乳膠球在重力場作用下,在水中能自發(fā)排列成周期性有序結(jié)構(gòu)。這種結(jié)構(gòu)的光子晶體工作頻率多落在微波波段。(1)精密機(jī)械加工法精密機(jī)械加工法以半導(dǎo)體工業(yè)成熟的技術(shù)為基礎(chǔ),是制備光子晶體最為穩(wěn)定可靠的方法。參見圖12??偠灾?,綜合利用光子晶體的各種優(yōu)越性能,光子晶體在低損耗反射鏡、分辨率極高的超棱鏡、光開關(guān)、光限幅、光放大器、選頻濾波器、偏振器、光聚焦器等方面都存在廣泛的應(yīng)用前景。該激光器以電流驅(qū)動,雖然閉值為300A,但為以后的研究提供了借鑒。除了上述的幾種方法以外,還有許多其他的方法來研究光子晶體。首先將本征方程化成三維的標(biāo)準(zhǔn)本征值問題,利用格林函數(shù)求解波導(dǎo)中的本征方程。它將平面波在倒格矢空間以平面波疊加的形式展開,將Maxwell方程組化成本征方程,然后求解得到本征頻率,本征頻率的合集即為光子能帶。光子處于光子晶體中時,光子在折射率不同的介質(zhì)中的波長是不一樣的,當(dāng)光子晶體中高低折射率介質(zhì)排列周期與一種電磁波的周期發(fā)生某些關(guān)聯(lián)時,這種電磁波就有可能不能在這種周期結(jié)構(gòu)中存在,這就是所謂的光子禁帶效應(yīng)。光子晶體的另一個主要特征是光子局域,當(dāng)光子晶體中引入雜質(zhì)或缺陷后,晶體原有的周期性被破壞,從而有可能在光子晶體帶隙中出現(xiàn)頻寬極窄的缺陷態(tài)。 光子帶隙是光子晶體的一個最基本的特性。雙光子聚合技術(shù)受到激光參數(shù)和有機(jī)材料組成的影響。然而,這樣獲得的光子晶體仍然存在者大量難以控制的在自組裝過程中產(chǎn)生的缺陷。結(jié)合其他技術(shù)可以在一維結(jié)構(gòu)的基礎(chǔ)上,比較精確地制作出工作于紅外和可見光波段甚至更短波長的光子晶體。在光子晶體的研究過程中,發(fā)展出多種制備方法,有微電子制備技術(shù)、半導(dǎo)體制造技術(shù)、膠體自組裝技術(shù)、多光子聚合技術(shù),以及全息光刻、分子生物組裝等方法??梢灶A(yù)見,光波導(dǎo)器件在未來的全光集成光路中將起到關(guān)鍵的作用。光子晶體光纖印(photon crystal fiber,PCF)是一種的帶有缺陷的二維光子晶體,它將光限制在缺陷內(nèi)傳播。因此一維光子晶體仍有很高的研究意義和應(yīng)用價值。如果只在一個方向具有周期結(jié)構(gòu),光子帶隙只可能出現(xiàn)在這個方向上,如果存在三維的周期結(jié)構(gòu),就有可能出現(xiàn)全方位的光子帶隙,落在帶隙中的光在任何方向都被禁止傳播。因此,為了使二十一世紀(jì)真正成為光子時代,就必須找到一種像半導(dǎo)體材料控制電子行為一樣的新型的控制光子行為的材料,而光子晶體是最有希望實現(xiàn)這一目的的材料。關(guān)鍵詞:一維光子晶體,光子帶隙,傳輸矩陣,傳輸特性AbstractPhotonic crystals is a permittivity structure with periodic to the difference of dimension in space,there are one,two and three dimension Photonic length of periodic structure is close to wavelength of also is called Photonic band gap materials and have many characters:Photonic band gap,spontaneous emission optics bistability,photonic localization and so band gap is important in the Photonic band gap,light can be transmitted and this give us a chance to control the of the characteristic of Photonic crystals,People are interested in the theoretical analyze and laboratorial research of Photonic ,the Photonic band gap is one of hotspot in research.To investigate the structure and characteristics of band gap,there are many methods to analyze Photonic crystals including the planewave expansion method, Green’s function method,finitedifference timedomain method and transfer matrix of me
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