發(fā)布時間：2018-04-03 07:17

  本文選題：自加速Airy光束　切入點：光束漂移　出處：《蘇州大學》2016年博士論文

【摘要】：在不考慮衍射擴散及相對論效應的情況下,人們普遍認為激光束在自由空間中都是沿直線傳播。2007年,美國物理學家D.N.Christodoulides等提出了自加速激光束的概念,用來描述沿彎曲路徑傳播的光束。他們產(chǎn)生了在實驗室范圍內(nèi)沿彎曲路徑傳播的一類新型激光束,稱為自加速Airy激光束。該光束具有三大奇異的特性:(1)在傳輸過程中保持局域光場結構不變;(2)具有自我修復的功能;(3)在傳播時能橫向加速,可以繞過障礙物。這些特性使其在光學清掃、彎曲等離子體通道的產(chǎn)生、時空光子彈、電子加速、微粒操控、全光路由和成像等領域有重要應用。另一方面,由于激光技術的發(fā)展,激光光束在光學系統(tǒng)以及湍流大氣中的傳輸和變換特性已經(jīng)成為激光應用研究中的重要課題。因此,新型激光光束的出現(xiàn)促使人們迫切地去研究它的傳輸變換特性,從而為其應用提供理論支持。本論文主要研究自加速Airy相關光場的構建及其傳輸特性,論文提出了幾種與Airy光束相關的光場模型并對其傳輸特性進行了探討,討論了Airy光束在湍流大氣傳輸過程中的漂移特點并提出了有效降低其漂移的幾種方案,最后在提出光束經(jīng)障礙物傳輸后自愈合能力量化標準的基礎上詳細比較了自加速Airy光束與無衍射貝塞爾高斯光束的自愈合能力。在第一章中介紹了自加速Airy光束的產(chǎn)生、特性、應用及其傳輸特性的研究背景,同時介紹了本論文的主要研究內(nèi)容和創(chuàng)新點。在第二章中介紹了激光傳輸?shù)幕纠碚摵虯iry函數(shù)相關的數(shù)學理論。在第三章中,提出了和Airy光束相關的幾種光場結構的理論模型,并且研究了這些光束的傳輸特性。首先,為解決Airy-Hermite-Gaussian激光模積分發(fā)散的問題,提出了有限能量的Airy-Hermite-Gaussian激光束模式,可以用來描述激光束通過彎曲波導結構后的光場,澄清了以前文獻中的觀點;其次,雙Airy光束因可方便操控其會聚焦點而在等離子熱點的控制等方面?zhèn)涫荜P注,但以前的研究一直直接從現(xiàn)象入手,沒有合適的理論模型,論文提出了簡潔而有效的數(shù)學模型,為研究其特性提供了方便;再次,目前由于受限于空間光調(diào)制器,實驗產(chǎn)生Airy光束均為小功率,論文用高斯光束合成Airy光束并討論了其在湍流大氣中的傳輸特性,為產(chǎn)生大功率的Airy光束提供了新思路,為其在大氣通信中的應用打下了基礎;最后,失調(diào)對激光束在精密光學系統(tǒng)中的傳輸影響很大,論文討論了自加速Airy光束通過失調(diào)光學系統(tǒng)的傳輸特性。在第四章中,研究了自加速Airy光束經(jīng)過湍流大氣傳輸后的光束漂移問題。論文另辟蹊徑,探討光束漂移和表示光束平滑特性的K參數(shù)之間的關系,發(fā)現(xiàn)無論Airy光束的特征尺度及波長、傳輸距離、湍流的內(nèi)尺度如何變化,Airy光束的漂移均在K=4.3時達到最大值。同時,發(fā)現(xiàn)降低Airy光束的相干性和加載渦旋位相可以有效降低Airy光束的漂移。論文還發(fā)現(xiàn)陣列的Airy光束比單個Airy光束以及相同陣列的高斯光束的漂移要明顯減小。這些結果為實際Airy光束在大氣通信中的應用提供了一些理論依據(jù)。在第五章中,量化研究了自加速Airy光束通過障礙物傳輸后的自愈合能力。無衍射激光束一般都有較強的自愈合能力。但是,以前的研究都是從傳輸后的形狀上大致判斷其自愈合能力,標準不很明確。論文對光束自愈合能力的量化描述提出了探索性的思考,并借助數(shù)學上描述希爾伯特空間中兩個矢量相似的數(shù)學工具來定量的比較不同光束的自愈合能力。由于無衍射貝塞爾高斯光束和自加速Airy光束是非常典型的結構光場,因此,詳細研究了自加速Airy光束和無衍射貝塞爾-高斯光束的自愈合能力,發(fā)現(xiàn)在一定范圍內(nèi),自加速Airy光束的自愈合能力比無衍射貝塞爾-高斯光束強。在第六章中我們進行了總結和展望。
[Abstract]:Without considering the diffraction diffusion and the relativity effect, people generally think that the laser beam in free space are spread along the straight line.2007, American physicist D.N.Christodoulides proposed the concept of self acceleration of the laser beam is used to describe the beam along the curved path of transmission. They produced in the laboratory range along the curved path a new type of laser beam, called self accelerating Airy laser beam. The beam has three properties: (1) the singular constant local light field structure in the transmission process; (2) with self repair function; (3) can spread in the lateral acceleration, can bypass the obstacles. These characteristics make in the optical clearing, bending of the plasma channel, spatiotemporal optical solitons, electron acceleration, particle manipulation, all-optical routing and imaging applications. On the other hand, with the development of laser technology, laser beam in the light Study of propagation and transformation characteristics of the system and the turbulent atmosphere has become an important research subject in laser application. Therefore, the emergence of new laser beam made it urgent to study its transmission characteristics, so as to provide theoretical support for its application. This paper mainly studies the self accelerating the construction of Airy light field and transmission characteristic. This paper puts forward several related Airy beam light field model and its transmission characteristics were discussed, discussed the drift characteristics of Airy beams in a turbulent atmosphere in the transmission process and puts forward some schemes to effectively reduce the drift, based on the proposed beam through the obstacle transmission after self-healing quantitative criteria for a detailed comparison with the self-healing non diffraction Bessel Gauss beam self accelerating Airy beam. The first chapter introduces the self accelerating Airy beam generation, characteristics and its application The research background of transmission characteristics, and introduces the main research contents and innovations. The second chapter introduces the basic theory of mathematical theory and the Airy function of laser transmission. In the third chapter, puts forward several related and Airy beam light field structure theory model, and the transmission characteristics of these beams the study. First, in order to solve the divergence problem of integral Airy-Hermite-Gaussian laser, Airy-Hermite-Gaussian laser beam model is proposed with finite energy, can be used to describe the laser beam through the waveguide structure after light field, clarify the views in the literature of the past; secondly, double Airy beam can be easily manipulated for its convergence and focus on hot plasma control has attracted much attention, but previous studies have directly from the start, no suitable theoretical models, this paper proposes a simple and effective mathematical model, Provide convenience for studying its characteristics; thirdly, at present, due to the limited spatial light modulator, the Airy beam generated for small power, with the synthesis of Airy and the Gauss beam beam in turbulent atmosphere transmission characteristics are discussed, and provides a new idea for the Airy beam from high power, for its application in atmospheric communication lay the foundation; finally, a great imbalance on the transmission effect of laser beam on the precision of optical system, this paper discusses the self accelerating Airy beam passing through a misaligned optical system characteristics. In the fourth chapter, the self accelerating Airy light beam through atmospheric turbulence after the beam drift problem. This is another way to explore the relationship between the beam drift and said beam smoothing characteristics of K parameters, found that the Airy beam characteristic scale and wavelength, transmission distance, how to scale turbulence changes, Airy beam drift in K =4.3 reached the maximum. At the same time, Airy were found to reduce the coherence of the beam and load the vortex phase can effectively reduce the Airy beam drift. The paper also found that Airy beam array to decrease than single Airy beam and Gauss beam drift the same array. These results provided some theoretical basis for the practical application of Airy beam in the atmosphere communication. In the fifth chapter, quantitative research on the self accelerating Airy beam through the self-healing obstacle after transmission ability. Without diffraction of a laser beam have strong self-healing ability. However, previous studies are from the transmission after the shape estimate the self healing ability, the standard is not very clear the paper on the beam. Quantitative self-healing description is proposed to explore thinking, and with the mathematical description of mathematical tools in Hilbert space two vector similar to the quantitative comparison of different light Beam self-healing ability. Due to the diffraction free Bessel Gauss beam and self accelerating Airy beam is very typical of the structure of the light field, therefore, a detailed study of the self accelerating Airy beam and the diffraction free Bessel - Gauss beam self-healing ability, to a certain extent, self healing Airy beam ability than non diffraction Bessel - Gauss beam. In the sixth chapter, we summarized and discussed.

【學位授予單位】：蘇州大學
【學位級別】：博士
【學位授予年份】：2016
【分類號】：TN24
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本文編號：1704166