基于表面等離激元金屬—介質(zhì)—金屬結(jié)構(gòu)的超材料吸收器的性質(zhì)研究
發(fā)布時(shí)間：2018-12-30 20:15
【摘要】：基于表面等離激元的金屬-介質(zhì)-金屬結(jié)構(gòu)超材料,可以將光場(chǎng)高度局域在納米尺度的中間介質(zhì)層微腔內(nèi),同時(shí)在特定的共振頻段內(nèi)具有完美吸收和高增益的近場(chǎng)強(qiáng)度等光學(xué)特性,在表面增強(qiáng)分子光譜、太陽(yáng)能電池、生物傳感以及光學(xué)吸收器件的設(shè)計(jì)優(yōu)化等領(lǐng)域內(nèi)被廣泛應(yīng)用和研究。本文的研究?jī)?nèi)容包括：金屬-介質(zhì)-金屬周期結(jié)構(gòu)超材料中表面等離激元的物理特性、完美吸收的物理機(jī)制以及介質(zhì)腔局域光場(chǎng)的形成機(jī)理和相關(guān)應(yīng)用問(wèn)題。本論文采用有限元分析法(HFSS)進(jìn)行了較為系統(tǒng)的研究。本文的具體工作和研究結(jié)果主要有：1、新穎地提出了金屬-介質(zhì)-金屬結(jié)構(gòu)所形成的“圓柱體介質(zhì)微腔”的概念并利用數(shù)值模擬的方法設(shè)計(jì)和研究了該結(jié)構(gòu)微腔的光學(xué)特性,尤其是準(zhǔn)確量化了微腔內(nèi)的能量密度。在正入射光的條件下,反射最小值(dip)落在中紅外區(qū)域,通過(guò)優(yōu)化結(jié)構(gòu)參數(shù),使其吸收率接近完美吸收,達(dá)到97%。此外,計(jì)算數(shù)據(jù)表明：這種亞波長(zhǎng)的多層結(jié)構(gòu)不僅可以將大部分的入射電磁場(chǎng)能量局域在中間介質(zhì)層,使其能量密度比增益高達(dá)到104,并且能夠得到較高的品質(zhì)因子Q,而Q值越大,表明在中紅外波段的表面增強(qiáng)分子吸收光譜和特征分子振動(dòng)模式的共振峰的線寬越窄,也即具有更強(qiáng)的電磁場(chǎng)增強(qiáng)效應(yīng)。再者,由于該結(jié)構(gòu)的對(duì)稱性,使其對(duì)入射光的極化方向具有不敏感的特性。2、設(shè)計(jì)了三波段的上層(TOP)為同心圓環(huán)的金屬-介質(zhì)-金屬結(jié)構(gòu)的完美吸收器,研究了在介質(zhì)腔內(nèi)所形成的“雙圓柱體介質(zhì)微腔”的近場(chǎng)增強(qiáng)和吸收特性。通過(guò)數(shù)值模擬分析和優(yōu)化,該結(jié)構(gòu)反射最小值(dip)位置落在16.65THz,20.65THz和25.65THz,其吸收率分別為95%,97%和95%,而且通過(guò)改變其結(jié)構(gòu)參數(shù),可以獨(dú)立或同時(shí)調(diào)制結(jié)構(gòu)的單個(gè)或多個(gè)共振頻率,極大地提高了調(diào)制效率和靈活性。經(jīng)計(jì)算,雙圓柱體介質(zhì)微腔內(nèi)的電磁場(chǎng)能量密度比增益高達(dá)10s。此外,由于雙微腔結(jié)構(gòu)的對(duì)稱性,故對(duì)入射光的極化方向同樣具有不敏感的特性,而上述這些特點(diǎn)使其非常適合作為多共振波段表面增強(qiáng)分子光譜的增強(qiáng)基底。3、研究了基于干涉原理的上層(TOP)為正方形的金屬-介質(zhì)-金屬結(jié)構(gòu)的長(zhǎng)方體介質(zhì)微腔內(nèi)的吸收和近場(chǎng)增強(qiáng)特性。在正入射條件下,通過(guò)優(yōu)化結(jié)構(gòu)參數(shù),可以得到中紅外范圍內(nèi)四帶吸收共振峰,最大吸收率可達(dá)98%,而這四個(gè)共振峰對(duì)應(yīng)著干涉駐波的基模和高階模式,它們的位置和近場(chǎng)強(qiáng)度可以通過(guò)改變結(jié)構(gòu)參數(shù)(尺寸、介質(zhì)材料)來(lái)進(jìn)行調(diào)制。由于生物化學(xué)功能基團(tuán)指紋譜的位置大部分在中紅外波段,因此將結(jié)構(gòu)的共振峰與功能基團(tuán)的吸收振動(dòng)峰位相重疊,就可以實(shí)現(xiàn)多通道的表面增強(qiáng)紅外吸收光譜(SEIRA)。
[Abstract]:Metallic-dielectric-metal structure metallics based on surface isoexcitons can localize the optical field height in nanoscale mesoscale microcavities. At the same time, it has the optical properties of perfect absorption and high gain near field intensity in the specific resonance frequency band, and enhances the molecular spectrum on the surface, solar cells, Biosensor and optical absorption device design optimization are widely used and studied. The contents of this paper include the physical properties of surface isopherons in metallic-dielectric-metal periodic structure supermaterials, the physical mechanism of perfect absorption, the formation mechanism of local light field in dielectric cavity and the related application problems. In this paper, the finite element analysis (HFSS) is used to carry out a systematic study. The main results of this paper are as follows: 1. The concept of "cylindrical dielectric microcavity" formed by metal-dielectric-metal structure is proposed, and the optical properties of the structure are designed and studied by means of numerical simulation. In particular, the energy density in the microcavity is accurately quantified. Under the condition of normal incident light, the minimum reflected (dip) falls in the mid-infrared region. By optimizing the structural parameters, the absorptivity is close to the perfect absorption and the absorption reaches 97%. In addition, the calculated data show that the sub-wavelength multilayer structure can not only localize most of the incident electromagnetic energy in the intermediate dielectric layer, so that the energy density ratio gain is up to 104, and the high quality factor Q can be obtained. The larger the Q value is, the narrower the line width of the absorption spectrum and the resonance peak of the characteristic molecular vibration mode in the mid-infrared band is, that is, the stronger the enhancement effect of electromagnetic field is. Furthermore, due to the symmetry of the structure, it is insensitive to the polarization direction of incident light. 2. A perfect absorber of metal-dielectric metal structure with concentric circular ring is designed for the upper layer (TOP) of three bands. The near field enhancement and absorption characteristics of a "double cylindrical dielectric microcavity" formed in a dielectric cavity are studied. Through numerical simulation analysis and optimization, the minimum reflection (dip) position of the structure falls to 16.65 THZ 20.65 THz and 25.65 THZ, the absorptivity is 95% and 95%, respectively, and by changing its structural parameters, The modulation efficiency and flexibility can be greatly improved by the single or multiple resonant frequencies which can be modulated independently or simultaneously. The calculation results show that the gain of electromagnetic field energy density is up to 10 s. Moreover, due to the symmetry of the double microcavity structure, it is also insensitive to the polarization direction of the incident light, which makes it very suitable for the enhancement of the multiresonance surface enhanced molecular spectra. The absorption and near field enhancement characteristics of a cuboid dielectric microcavity with a metal dielectric structure with a square upper (TOP) based on the interference principle are studied. Under the normal incidence condition, by optimizing the structural parameters, the four-band absorption resonance peak in the mid-infrared range can be obtained, and the maximum absorptivity can be as high as 98. The four resonance peaks correspond to the fundamental mode and the higher-order mode of the interference standing wave. Their position and near-field strength can be modulated by changing structural parameters (dimensions, dielectric materials). Since the position of the biochemistry functional group fingerprint spectrum is mostly in the mid-infrared band, therefore, by overlapping the resonance peak of the structure with the absorption vibration peak of the functional group, the multi-channel surface-enhanced infrared absorption spectrum (SEIRA). Can be realized.
【學(xué)位授予單位】：南京師范大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2015
【分類號(hào)】：O441;TB34
[Abstract]:Metallic-dielectric-metal structure metallics based on surface isoexcitons can localize the optical field height in nanoscale mesoscale microcavities. At the same time, it has the optical properties of perfect absorption and high gain near field intensity in the specific resonance frequency band, and enhances the molecular spectrum on the surface, solar cells, Biosensor and optical absorption device design optimization are widely used and studied. The contents of this paper include the physical properties of surface isopherons in metallic-dielectric-metal periodic structure supermaterials, the physical mechanism of perfect absorption, the formation mechanism of local light field in dielectric cavity and the related application problems. In this paper, the finite element analysis (HFSS) is used to carry out a systematic study. The main results of this paper are as follows: 1. The concept of "cylindrical dielectric microcavity" formed by metal-dielectric-metal structure is proposed, and the optical properties of the structure are designed and studied by means of numerical simulation. In particular, the energy density in the microcavity is accurately quantified. Under the condition of normal incident light, the minimum reflected (dip) falls in the mid-infrared region. By optimizing the structural parameters, the absorptivity is close to the perfect absorption and the absorption reaches 97%. In addition, the calculated data show that the sub-wavelength multilayer structure can not only localize most of the incident electromagnetic energy in the intermediate dielectric layer, so that the energy density ratio gain is up to 104, and the high quality factor Q can be obtained. The larger the Q value is, the narrower the line width of the absorption spectrum and the resonance peak of the characteristic molecular vibration mode in the mid-infrared band is, that is, the stronger the enhancement effect of electromagnetic field is. Furthermore, due to the symmetry of the structure, it is insensitive to the polarization direction of incident light. 2. A perfect absorber of metal-dielectric metal structure with concentric circular ring is designed for the upper layer (TOP) of three bands. The near field enhancement and absorption characteristics of a "double cylindrical dielectric microcavity" formed in a dielectric cavity are studied. Through numerical simulation analysis and optimization, the minimum reflection (dip) position of the structure falls to 16.65 THZ 20.65 THz and 25.65 THZ, the absorptivity is 95% and 95%, respectively, and by changing its structural parameters, The modulation efficiency and flexibility can be greatly improved by the single or multiple resonant frequencies which can be modulated independently or simultaneously. The calculation results show that the gain of electromagnetic field energy density is up to 10 s. Moreover, due to the symmetry of the double microcavity structure, it is also insensitive to the polarization direction of the incident light, which makes it very suitable for the enhancement of the multiresonance surface enhanced molecular spectra. The absorption and near field enhancement characteristics of a cuboid dielectric microcavity with a metal dielectric structure with a square upper (TOP) based on the interference principle are studied. Under the normal incidence condition, by optimizing the structural parameters, the four-band absorption resonance peak in the mid-infrared range can be obtained, and the maximum absorptivity can be as high as 98. The four resonance peaks correspond to the fundamental mode and the higher-order mode of the interference standing wave. Their position and near-field strength can be modulated by changing structural parameters (dimensions, dielectric materials). Since the position of the biochemistry functional group fingerprint spectrum is mostly in the mid-infrared band, therefore, by overlapping the resonance peak of the structure with the absorption vibration peak of the functional group, the multi-channel surface-enhanced infrared absorption spectrum (SEIRA). Can be realized.
【學(xué)位授予單位】：南京師范大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2015
【分類號(hào)】：O441;TB34
【相似文獻(xiàn)】
相關(guān)期刊論文 前10條
1 ;光學(xué)左手超材料捕獲彩虹取得突破[J];光機(jī)電信息;2009年11期
2 聞孺銘;李凌云;韓克武;孫曉瑋;;微波超材料隱形結(jié)構(gòu)及其新型快速實(shí)驗(yàn)方案[J];物理學(xué)報(bào);2010年07期
3 樹(shù)華;;可以用光進(jìn)行控制的超材料[J];物理;2012年12期
4 丁敏;薛暉;吳博;孫兵兵;劉政;黃志祥;吳先良;;基于電磁超材料的兩種等效參數(shù)提取算法的比較分析[J];物理學(xué)報(bào);2013年04期
5 弓巧俠;劉曉e，
本文編號(hào)：2396084
本文鏈接：http://sikaile.net/kejilunwen/cailiaohuaxuelunwen/2396084.html
最近更新
教材專著
