發(fā)布時間：2018-04-17 15:40

  本文選題：超材料 + 吸波體��； 參考：《北京化工大學(xué)》2015年碩士論文

【摘要】：超材料(metamaterial)是一種亞波長結(jié)構(gòu)周期排列而成的人工材料,擁有常規(guī)材料不能實現(xiàn)的奇異電磁特性,在隱身斗篷、納米光學(xué)成像、微型諧振器、定向發(fā)射天線、熱輻射探測器、太陽能轉(zhuǎn)換器、彎曲波導(dǎo)等領(lǐng)域具有極大的應(yīng)用潛力。本文以發(fā)展新型超材料為目標(biāo),系統(tǒng)研究了三角型吸波體、“豐”型零折射超材料、“回”型負折射超材料、雙“E”型超材料、“中”型負折射超材料和銅錢型超材料等六種材料,計算了其等效電磁參數(shù),分析了結(jié)構(gòu)與電磁特性的依賴關(guān)系,揭示了這些超常電磁特性的微波響應(yīng)機理。其中重點開展了三角型超材料吸波體和銅錢型超材料的電磁特性研究。對于三角型超材料吸波體：三角型MMA厚度為波長的1/8,遠小于普通電損耗吸波介質(zhì)厚度(λ/4),并且吸收性能得到了極大提高。吸收峰頻率隨介質(zhì)厚度和金屬厚度的減小而藍移,與原胞間縫寬成線性關(guān)系,這種吸波性能對縫寬的線性依賴關(guān)系使得調(diào)控微波吸收頻帶更為簡便。該吸波體的損耗以介質(zhì)損耗為主,歐姆損耗為輔,在熱探測器、傳感器、微波衰減器件上具有潛在的應(yīng)用前景。銅錢型結(jié)構(gòu)的超材料呈現(xiàn)出一個負折射帶(品質(zhì)因數(shù)為5.6)和兩個零折射帶(一個寬頻帶和一個低損耗頻帶),在多頻段、多功能、不同損耗微波器件應(yīng)用中具有明顯優(yōu)勢。我們深入探討了銅錢環(huán)、金屬線與共振頻率的關(guān)系,建立了銅錢型超材料的電等離子體頻率和磁等離子體頻率模型,分析了銅錢型超材料負折射和零折射的產(chǎn)生機理,為新型超材料研究與發(fā)展提供了參考；基于零折射特性的研究結(jié)果,提出了實現(xiàn)零折射率的通用判據(jù),即同時滿足條件ε'μ"+μ'ε"≈0和μ'ε'-ε"μ"0,為寬帶零折射超材料的設(shè)計提供了理論依據(jù)。此外,研究了零折射超材料在彎曲同軸波導(dǎo)、T形微帶線、喇叭天線中的應(yīng)用。
[Abstract]:Metamaterial) is an artificial material with a periodic subwavelength structure, with singular electromagnetic properties that cannot be achieved by conventional materials, in stealth cloaks, nano-optical imaging, microresonators, directional emission antennas, thermal radiation detectors.Solar energy converter, curved waveguide and other fields have great application potential.Aiming at the development of new metamaterials, this paper systematically studies the triangular absorber, "Feng" type zero refraction supermaterial, "return" type negative refraction supermaterial, and double "E" type supermaterial.Six kinds of materials, such as "medium" negative refraction metamaterials and copper-Qian metamaterials, are calculated. The dependence of structure on electromagnetic properties is analyzed, and the microwave response mechanism of these supernormal electromagnetic properties is revealed.The electromagnetic properties of triangular supermaterials and copper-Qian supermaterials are studied.For triangular supermaterial, the thickness of triangular MMA is 1 / 8 of the wavelength, which is much smaller than that of ordinary dielectric absorber (位 / 4), and the absorption performance is greatly improved.The absorption peak frequency shifts blue with the decrease of the dielectric thickness and the metal thickness, and is linearly related to the original intercellular slit width. The linear dependence of the absorption performance on the slit width makes it easier to control the microwave absorption band.The loss of the absorber is mainly dielectric loss, ohmic loss is auxiliary, and has potential application prospect in thermal detector, sensor and microwave attenuation device.The copper-Qian type metamaterials show a negative refraction band (quality factor 5.6) and two zero refraction bands (one wide band and one low loss band), which have obvious advantages in the application of multi-band, multi-function and different loss microwave devices.The relationship between copper ring, wire and resonance frequency is discussed in depth. The electric plasma frequency and magnetic plasma frequency model of copper Qian type supermaterial are established, and the generation mechanism of negative refraction and zero refraction of copper Qian type supermaterial are analyzed.It provides a reference for the research and development of new metamaterials, and based on the research results of zero refraction, a general criterion for realizing zero refraction index is proposed.The conditions 蔚'渭 "渭'蔚" 鈮，

本文編號：1764212