石墨烯於混合光聲生物感測器和太赫茲電漿波導之應用

Abstract

隨著科技發展進步，人類對電磁頻譜上最後一塊拼圖「太赫茲」越來越受重視，因此太赫茲的元件發展也顯得非常重要，本篇論文結合二維材料石墨烯的費米能階具有調變性的特點，利用有限元素法進行二維的石墨烯表面電漿子的元件設計與應用，並且分成兩個部分進行研究:第一部分石墨烯表面電漿波導設計。由於石墨烯的能帶結構特殊因此又稱為半金屬，能夠產生表面電漿在石墨烯與介電質之間傳遞；又因為石墨烯的邊界條件使橫向電波(Transverse Electric Wave, TE)也能夠產生表面電漿在石墨烯表面，不同於傳統只有在橫向磁波(Transverse Magnetic Wave, TM)才能夠在金屬表面產生表面電漿；並探討其傳遞距離(Propagation Length)與衰減深度(Decay Length)與TM極化表面電漿比較。

第二部分混合光聲生物感測器。由於石墨烯混合電漿生物感測器只能針對樣品的折射率做測量，所以當兩個待測物的折射率相同時會無法分辨兩者待測物，因此結合聲波於感測器上，利用不同待測物所固有的應力係數區分待測物，以達到更有效率的辨識待測物來源。As the progress of technology, Terahertz becomes more important in human history. Therefore, the development of terahertz components is also very important. In this thesis we combines the characteristics of the modulation of the Fermi level of the two-dimensional material of graphene, uses the finite-element analysis to design and apply graphene surface plasmon components, and divides it into two parts for research:The first part is design the graphene surface plasmon waveguide in THz region. Because of the special energy band structure of graphene, it is also called semimetal, which can generate surface plasmon on the interface between graphene and dielectric. Since the boundary conditions of graphene, the transverse electric wave (TE) can also generate surface plasma on the graphene and dielectric interface. Different from the traditional method of only transverse magnetic wave (TM) can generate surface plasmon on the metal and dielectric surface. And at final chapter we discuss its propagation length and decay length and compared of the TE and TM polarized surface plasmon.The second part is a hybrid optical-acoustic biosensor biosensor. Since the graphene hybrid plasma biosensor can only measure the refractive index of the sample, when the refractive indices of the two analytes are the same, it will not be able to distinguish between the two analytes. Therefore, combined the acoustic wave on the biosensor, with the inherent stress modulus of different analysis distinguishing the analytes. Achieve more efficient identification the analytes by using hybrid optical-acoustic biosensor.