Structural SPR Tunability of Metal@Graphene Core–Shell Nano-Needle and Nano-Disk
- 189 Downloads
In present paper, a design of the graphene-coated metal (Ag/Au/Cu) nano-disk (2D) and nano-needle (1D) has been studied within the quasi-static approximation. The core@shell nano-geometries display dual dipolar plasmonic resonances which can be influenced by the resonance coupling between the plasmonic modes of the core and shell. These results indicate two different types of plasmon coupling and their wide range of SPR tunabilty: one is symmetric (1100~1600 nm) and other is anti-symmetric coupling (700~1120 nm). The resonance tunability in the symmetric and the anti-symmetric modes are strongly dependent on the sizes of the metallic core (semi major axes of the core 16~24 nm), graphene mono layer (GML) shell thickness (0.01~0.05 nm), and the ASR (0.06~0.12) of the core@shell nano-structure. Metal@GML nano-geometries are embedded in organic environment of the two different polymer matrices PCDTBT:PC71BM (εm=3.36) and PTB7:PC71BM (εm=3.47) that show an appropriate SPR tunability instead of non-coated metallic nano-disk and nano-needle. We have analyzed optical properties of coated and non-coated nano-geometries in terms of SPR tunability and extinction efficiency (Qext). For a fixed ASR, the symmetric modes of nano-disks have a wide range of SPR tunability in the IR range, while for nano-needles, both the modes having wide range of tunability in visible to IR region. Similarly for a fix TGML, the symmetric modes of nano-needles have a high tunability in the IR region. Hence, both the nano-geometries having a great potential for light trapping in the desirable range of wavelength of solar spectrum.
KeywordsCore@shell nano-disk Core@shell nano-needle Graphene monolayer Surface plasmon resonances Extinction efficiency SPR tunability
One of the authors Shivani Bhardwaj is thankful to MNRE India for providing the financial support for this research.
- 3.Kreibig U, Vollmer M (2013) Optical properties of metal clusters, vol 25. Springer Science & Business MediaGoogle Scholar
- 4.Maier SA (2007) Plasmonics: fundamentals and applications. Springer Science & Business MediaGoogle Scholar
- 12.Bhardwaj S, Uma R, Sharma R (2016) A study of metal@ graphene Core–Shell spherical Nano-geometry to enhance the SPR Tunability: influence of graphene monolayer Shell thickness. Plasmonics:1–9Google Scholar
- 17.Freitag M, Low T, Zhu W, Yan H, Xia F, Avouris P (2013) Photocurrent in graphene harnessed by tunable intrinsic plasmons. arXiv preprint arXiv:13060593Google Scholar
- 18.Zhou W, Lee J, Nanda J, Pantelides ST, Pennycook SJ, Idrobo J-C (2012) Atomically localized plasmon enhancement in monolayer graphene. Nat Nano 7(3):161–165 http://www.nature.com/nnano/journal/v7/n3/abs/nnano.2011.252.html#supplementary-information CrossRefGoogle Scholar
- 23.Echtermeyer T, Britnell L, Jasnos P, Lombardo A, Gorbachev R, Grigorenko A, Geim A, Ferrari A, Novoselov K (2011) Strong plasmonic enhancement of photovoltage in graphene. arXiv preprint arXiv:11074176Google Scholar
- 24.Stylianakis M, Konios D, Kakavelakis G, Charalambidis G, Stratakis E, Coutsolelos A, Kymakis E, Anastasiadis S (2015) Efficient ternary organic photovoltaics incorporating a graphene-based porphyrin molecule as a universal electron cascade material. Nano 7(42):17827–17835Google Scholar
- 27.Bohren CF, Huffman DR (2008) Absorption and scattering of light by small particles. John Wiley & SonsGoogle Scholar
- 28.Palik ED (1998) Handbook of optical constants of solids, vol 3. Academic pressGoogle Scholar
- 30.Bao Q, Zhang H, Wang B, Ni Z, Lim CHYX, Wang Y, Tang DY, Loh KP (2011) Broadband graphene polarizer. Nat Photonics 5(7):411–415 http://www.nature.com/nphoton/journal/v5/n7/abs/nphoton.2011.102.html#supplementary-information CrossRefGoogle Scholar
- 35.Chew WC (1995) Waves and fields in inhomogeneous media, vol 522. IEEE press, New YorkGoogle Scholar