پديد آورنده :
رئيسي، شايسته
عنوان :
بررسي خواص پلاسموني در آرايه هاي نانوساختار فلزي طلا و نقره
مقطع تحصيلي :
كارشناسي ارشد
محل تحصيل :
اصفهان : دانشگاه صنعتي اصفهان
صفحه شمار :
سيزده، 72ص.:.مصور (رنگي)، جدول، نمودار
استاد راهنما :
پيمان صاحب سرا
استاد مشاور :
حميده شاكري پور
توصيفگر ها :
پلاسمون سطحي موضعي , حساسيت , پلاسمونيك , نظريه ماي , لومريكال , حسگري
استاد داور :
جواد هاشمي فر، مهدي رنجبر
تاريخ ورود اطلاعات :
1400/11/17
تاريخ ويرايش اطلاعات :
1400/11/18
چكيده فارسي :
از ﺟﺬابﺗﺮﯾﻦ ﺧﺼﻮﺻﯿﺎت ﻧﺎﻧﻮذرات ﻓﻠﺰي، وﯾﮋﮔﯽﻫﺎي اﭘﺘﯿﮑﯽ آنﻫﺎ اﺳﺖ ﮐﻪ ﺑﻪ ﻧﺴﺒﺖ اﻧﺪازه، ﺷﮑﻞ و ﺟﻨﺲ
ﻧﺎﻧﻮذرات و ﻫﻤﭽﻨﯿﻦ ﻣﺤﯿﻂ اﻃﺮاف ﻧﺎﻧﻮذره ﻣﺘﻐﯿﺮ اﺳﺖ. وﻗﺘﯽ ﻓﻠﺰات وارد ﺣﻮزهي ﻧﺎﻧﻮ ﻣﯽﺷﻮﻧﺪ ﺧﻮاص اﭘﺘﯿﮑﯽ و ﻧﻮري ﭘﯿﭽﯿﺪه و ﻣﺘﻨﻮﻋﯽ را از ﺧﻮدﺷﺎن ﻧﺸﺎن ﻣﯽدﻫﻨﺪ، ﮐﻪ ﻧﺎﺷﯽ از ﺑﻪ وﺟﻮد آﻣﺪن و ﯾﺎ ﺗﺤﺮﯾﮏ ﭘﻼﺳﻤﻮنﻫﺎي ﺳﻄﺤﯽ در
آنﻫﺎ اﺳﺖ. ﺑﺎ ﭘﯿﺪاﯾﺶ ﻓﻨﺎوري ﻧﺎﻧﻮ، اﺳﺘﻔﺎده از ﺳﺎﺧﺘﺎرﻫﺎي ﭘﻼﺳﻤﻮﻧﯿﮑﯽ در اﺑﻌﺎد ﺧﯿﻠﯽ ﮐﻮﭼﮏ اﻣﮑﺎنﭘﺬﯾﺮ ﺷﺪه اﺳﺖ.
ﭘﯿﺸﺮﻓﺖ ﺟﺎذبﻫﺎي ﭘﻼﺳﻤﻮﻧﯿﮑﯽ ﺑﺎﻋﺚ ﮐﺎرﺑﺮدﻫﺎي زﯾﺎدي ﺷﺪه اﺳﺖ. ﺧﻮاص ﻧﻮري ﮐﻪ از ﺗﺤﺮﯾﮏ ﭘﻼﺳﻤﻮنﻫﺎي ﺳﻄﺤﯽ در ﻧﺎﻧﻮذرات ﻓﻠﺰي ﺑﻪ وﺟﻮد ﻣﯽآﯾﺪ را ﻧﻤﯽﺗﻮان در ﺳﺎﯾﺮ ﻣﻮاد
اﭘﺘﯿﮑﯽ ﺑﻪ آﺳﺎﻧﯽ ﺑﻪ دﺳﺖ آورد. اﯾﻦ ﻣﻮﺿﻮع ﺑﺎﻋﺚ ﺑﻪ ﮐﺎر ﺑﺮدن آن در ﻃﯿﻒ وﺳﯿﻌﯽ از زﻣﯿﻨﻪﻫﺎي ﻣﺨﺘﻠﻒ ﻣﯽﺷﻮد. ﻧﺎﻧﻮﺣﯿﮕﺮﻫﺎي ﭘﻼﺳﻤﻮﻧﯿﮑﯽ، ﺑﺮﭘﺎﯾﻪي ﺑﺮرﺳﯽ ﻃﯿﻒ ﺟﺬﺑﯽ ﺳﺎﺧﺘﺎرﻫﺎ ﺗﺤﻠﯿﻞ ﻣﯽﺷﻮﻧﺪ. اﯾﻦ ﻧﺎﻧﻮﺣﺴﮕﺮﻫﺎ ﺑﺎ اﺳﺘﻔﺎده ﺗﺸﺪﯾﺪ اﻣﻮاج ﭘﻼﺳﻤﻮن ﺳﻄﺤﯽ در ﻣﺤﺪودهي ﻣﺮز ﺑﯿﻦ دياﻟﮑﺘﺮﯾﮏ و ﻓﻠﺰ، ﮐﻪ ﺑﺎﻋﺚ ﺗﺠﻤﻊ ﻧﻮر در ﺳﺎﺧﺘﺎرﻫﺎﯾﯽ ﺑﺎ اﺑﻌﺎد زﯾﺮ ﻃﻮل ﻣﻮج ﻣﯽﺷﻮد ﻋﻤﻞ ﻣﯽﮐﻨﻨﺪ. ﺑﺎ ﺗﺤﺮﯾﮏ ﮐﺮدن ﻧﺎﻧﻮﺣﺴﮕﺮ، اﻟﮑﺘﺮونﻫﺎﯾﯽ ﮐﻪ ﺑﺮ روي ﺳﻄﺢ ﻓﻠﺰ ﻗﺮار دارﻧﺪ ﺗﺤﺮﯾﮏ ﻣﯽﺷﻮﻧﺪ و ﻃﯿﻒ ﻧﻮر ﺑﺎزﺗﺎب ﻣﯽﺷﻮد ﮐﻪ ﻣﻨﺠﺮ ﺑﻪ ﺗﻐﯿﯿﺮ ﻧﻮر ﺟﺬب ﺷﺪه ﻣﯽﺷﻮد. ﺑﻪ ﻣﯿﺰان ﺗﻐﯿﯿﺮاﺗﯽ ﮐﻪ در ﻃﯿﻒ ﺟﺬب رخ ﻣﯽدﻫﺪ
ﮐﻪ دﻟﯿﻞ آن ﺟﺬب ﻣﺎده اﺳﺖ، ﻧﻤﻮﻧﻪ را ﻣﯽﺗﻮان ﺗﺸﺨﯿﺺ داد. در اﯾﻦ ﭘﺎﯾﺎن ﻧﺎﻣﻪ، ﺷﺒﻪذرهﻫﺎي ﭘﻼﺳﻤﻮنﻫﺎ و ﻧﺤﻮهي ﺗﺤﺮﯾﮏ آنﻫﺎ در ﻧﺎﻧﻮذرات، در ﭼﺎرﭼﻮب ﻧﻈﺮﯾﻪي ﻣﺎي ﺑﺮرﺳﯽ ﻣﯽﮔﺮدد. ﻋﻼوه ﺑﺮ آن ﻣﯿﺰان اﺛﺮﮔﺬاري ﻣﺘﻐﯿﺮﻫﺎي اﻧﺪازه و ﺟﻨﺲ ﻧﺎﻧﻮذرهﻫﺎي ﻓﻠﺰي و ﻫﻤﯿﻨﻄﻮر ﺿﺮﯾﺐ ﺷﮑﺴﺖ ﻣﺤﯿﻂ
اﻃﺮاف ﺑﺮ روي ﺑﺴﺎﻣﺪ ﺗﺸﺪﯾﺪ ﭘﻼﺳﻤﻮن ﺳﻄﺤﯽ ﺟﺎﯾﮕﺰﯾﺪه ﺑﻪ ﻃﻮر ﺗﺤﻠﯿﻠﯽ و ﻋﺪدي ﻣﻮرد ﺑﺮرﺳﯽ ﻗﺮار ﮔﺮﻓﺘﻪ اﺳﺖ. در اﯾﻦ ﭘﺎﯾﺎن ﻧﺎﻣﻪ ﺗﺤﻘﯿﻘﺎﺗﯽ ﺑﺮ روي ﻧﺎﻧﻮآراﯾﻪﻫﺎ و ﺗﺄﺛﯿﺮ ﻗﺮارﮔﺮﻓﺘﻦ ﻧﺎﻧﻮذرات ﺑﻪ ﺻﻮرت آراﯾﻪاي ﺑﺮ روي ﺗﺸﺪﯾﺪ
ﭘﻼﺳﻤﻮن ﺳﻄﺤﯽ ﺻﻮرت ﮔﺮﻓﺘﻪ اﺳﺖ. ﺑﺎ ﻣﺘﻐﯿﺮ در ﻧﻈﺮ ﮔﺮﻓﺘﻦ ﭘﺎراﻣﺘﺮﻫﺎي ﻣﺨﺘﻠﻒ از ﺟﻤﻠﻪ ﻓﺎﺻﻠﻪي ﺑﯿﻦ ﻧﺎﻧﻮذرات، ﺷﮑﻞ و ﺟﻨﺲ آنﻫﺎ ﺟﺎﺑﺠﺎﯾﯽ ﻗﻠﻪﻫﺎي ﭘﻼﺳﻤﻮﻧﯽ را ﻣﻮرد ﺑﺮرﺳﯽ و ﺑﺤﺚ ﻗﺮار دادهاﯾﻢ و ﺑﺎ اﺳﺘﻔﺎده از ﺗﻐﯿﯿﺮاﺗﯽ ﮐﻪ در ﻗﻠﻪﻫﺎي ﭘﻼﺳﻤﻮﻧﯽ اﯾﺠﺎد ﺷﺪه اﺳﺖ، ﻣﯿﺰان ﺣﺴﺎﺳﯿﺖ ﺳﺎﺧﺘﺎرﻫﺎي ﭘﯿﺸﻨﻬﺎدي را ﺑﺮرﺳﯽ ﮐﺮدهاﯾﻢ و ﺑﻬﺘﺮﯾﻦ ﺳﺎﺧﺘﺎر را
ﺑﺮاي ﺣﺴﮕﺮي اﻧﺘﺨﺎب ﮐﺮدهاﯾﻢ.
چكيده انگليسي :
One of the interesting properties of metal nanoparticles is their optical properties which varies with nanoparticles shape, size and material and refractive index or dielectric constant of surrounding medium of nanopar- ticle. Nanostructured metals show very complex and interesting optical properties which is because of the excitation of surface plasmons in them. The excitation of surface plasmons in metallic nanoparticles induces op- tical properties hardly achievable in other optical materials, yielding a wide range of applicatins in many fields. Surface plasmon resonance is the most outstanding optical property of metallic nanostructures. In physics,a plasmonis a quantum of plasma oscillation just as photons and phonons are quantizations of electromagnetic and mechanical vibration, respec- tively.The plasmon for medat the interface of a metal and a dielectric are said surface plasmon and resonant excitation of a collective oscilation of the conduction band electrons in the nanoparticles when the nanoparticle is illuminated by a incident electromagnetic wave is termed localized sur- face plamon. In other words, surface palsmons are collective oscilation of conduction electrons by a optical signal on the surface of a metal. By con- sidering the importance of plasmons in metal nanoparticles, in this thesis we investigate how the surface plasmons are excited in metal nanoparti- cles as well as optical properties of surface plasmons in metal nanoparticles which make them uniqe are investigated. In this thesis, in additionof intro- ducing quasiparticle plasmon and mechanisms of its excitation in the case of bulk metal, interface of metal and dielectric and aslo in nanoparticles; using Mie theory, the effects of nanoparticle size and material of the metal nanoparticles are made of and also refractive index or dielectric constant of surrounding medium of nanoparticle on the localized surface plasmon frequency are investigated both numerically and analitically.
In this dissertation, research has been done on nanoarrays and the effect of nanoparticles as an array on surface plasmon intensification. By consid- ering various parameters such as the distance between nanoparticles, their shape and material, we have studied and discussed the displacement of plasmonic peaks, and using the changes that have occurred in plasmonic peaks, we have examined the sensitivity of the proposed structures and the best structure selected for sensor.
استاد راهنما :
پيمان صاحب سرا
استاد مشاور :
حميده شاكري پور
استاد داور :
جواد هاشمي فر، مهدي رنجبر
