【摘要】：自從上世紀(jì)60年代第一臺激光器被發(fā)明以來,人們可以將強(qiáng)度很高、單色性很好的激光光束與物質(zhì)相互作用,從而觀察到一系列前所未有的新奇現(xiàn)象,如光學(xué)整流、差頻、和頻、倍頻、混頻、受激拉曼散射、光束自聚焦等等,為了深入了解這些有趣的現(xiàn)象,非線性光學(xué)理論便應(yīng)運(yùn)而生了。 隨著非線性光學(xué)的研究日趨成熟,人們開始逐漸將已取得的研究成果廣泛應(yīng)用到各個科技領(lǐng)域中,如利用光學(xué)非線性效應(yīng)在光纖中產(chǎn)生光孤子、通過交叉相位和自相位調(diào)制制作全光開光、制造讀取速度更快,保真度更高的光存儲器件等等,這些應(yīng)用在未來的量子計(jì)算與量子通信領(lǐng)域?qū)a(chǎn)生巨大作用�；诜蔷�性光學(xué)豐富并且重要的應(yīng)用價值,越來越多的人們開始關(guān)注如何增強(qiáng)與調(diào)控激光與介質(zhì)相互作用時的光學(xué)非線性效應(yīng)。近年來人們逐漸將非線性光學(xué)的研究拓展至量子水平,比如在單光子條件和微腔中探究非線性增強(qiáng)的量子相干效應(yīng)等等。 我們采用密度矩陣方法對N型四能級系統(tǒng)與三個光場的相互作用過程進(jìn)行了數(shù)值模擬,計(jì)算中考慮了多普勒效應(yīng)、碰撞增寬等多種實(shí)際效應(yīng)的影響；并用綴飾態(tài)理論進(jìn)行了分析和解釋。實(shí)驗(yàn)上,自行搭建了光學(xué)腔系統(tǒng),通過腔透射譜的不對稱度獲得了N型四能級系統(tǒng)的自克爾非線性系數(shù),并估算得到了該系數(shù)的絕對值。同時,測量了不同調(diào)節(jié)場強(qiáng)度下自克爾非線性系數(shù)隨探測場頻率的變化,所得結(jié)果和理論計(jì)算基本吻合。對兩者之間存在差異的原因我們也進(jìn)行了較為合理的分析。本研究將為光孤子傳輸及基于自相位調(diào)制的部分應(yīng)用提供新思路,從而更好地應(yīng)用在光纖通信、全光開關(guān)等。
[Abstract]:Since the invention of the first laser in 1960s, people can interact with matter with high intensity and good monochromaticity, and a series of unprecedented novel phenomena, such as optical rectification, difference frequency, sum frequency, frequency doubling, mixing, stimulated Raman scattering, beam self-focusing and so on, have been observed. In order to deeply understand these interesting phenomena, nonlinear optical theory emerges as the times require. With the maturity of nonlinear optics, people begin to widely apply the existing research results to various scientific and technological fields, such as the generation of optical solitons in optical fiber by optical nonlinear effect, the fabrication of all-optical open light by cross-phase and self-phase modulation, the fabrication of optical memory devices with faster reading speed and higher fidelity, and so on. These applications will play a great role in the field of quantum computing and quantum communication in the future. Based on the rich and important application value of nonlinear optics, more and more people begin to pay attention to how to enhance and regulate the optical nonlinear effect of laser-dielectric interaction. In recent years, the study of nonlinear optics has been gradually extended to the quantum level, such as exploring the quantum coherence effect of nonlinear enhancement in single-photonic conditions and microcavities. In this paper, the interaction process between N-type four-level system and three light fields is simulated by density matrix method, and the effects of Doppler effect, collision broadening and other practical effects are taken into account in the calculation, and the affixed state theory is used to analyze and explain the interaction between N-type four-level system and three light fields. In the experiment, the optical cavity system is built, and the self-Kerr nonlinear coefficient of the N-type four-level system is obtained by the asymmetry of the cavity transmission spectrum, and the absolute value of the coefficient is estimated. At the same time, the variation of self-Kerr nonlinear coefficient with the frequency of detection field under different intensity of regulating field is measured, and the results are in good agreement with the theoretical calculation. We also make a reasonable analysis of the reasons for the differences between the two. This study will provide a new idea for optical soliton transmission and some applications based on self-phase modulation, so as to be better used in optical fiber communication, all-optical switch and so on.
【學(xué)位授予單位】：華東理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TN248

【參考文獻(xiàn)】

相關(guān)博士學(xué)位論文 前1條

1 李淑靜;多能級原子系統(tǒng)中量子相干增強(qiáng)的弱光非線性[D];山西大學(xué);2008年

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本文編號：2497858