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Физико-технические проблемы в науке, промышленности и медицине (ФТПНМ-2019). Сборник научных трудов Международной научно-практической конференции студентов, аспирантов и молодых ученых (30 сентября - 04 октября 2019г.)
The high mobility of charge carriers in graphene makes it promising and prospective material for using for various applications as a future base for nanoelectronics and possible replacement of silicon in integrated circuits, and contributes to the creation of radioelectronic devices and arrangements microwave, Sub-THz and THz-bands. Pro-gress in the production and formation of curly graphene represents great opportunities to create tunable microwave, Sub-THz, THz metamaterials and integrated plasmonic devices with potential applications in the filters and polar-izers.
In this report investigated the graphene metasurfaces for transmission of radiation, induced by plasmons in the THz range, whose cell consists of structure based on a graphene ring and graphene nanotape. As graphene rings, and graphene nanotapes create regimes of transmittance – transparency windows induced by electric dipole reso-nances. Weak hybridization between this two elements results to appearance of new transparency window induced by plasmons that can be controlled by changing the geometric dimensions of the graphene-based metasurfaces cell structure. The resonance frequency of the transparency window can be dynamically rearranged over wide band of THz frequencies, altering the chemical potential (Fermi energy) of graphene by applying of an external electric field instead of re-fabricating the nanostructures.
Figure 1 shows the graphene-based metasurfaces cell structures to demonstrate the phenomena of Plasmon-in-duced radiation. The main unit cell of the metasurfaces consists of graphene ring and graphene nanotape. The inner and outer radii of the graphene ring are r1 = 2 μm and r2 = 3.2 μm. The length of the nanotape is L=9 microns, and the width is W = 0.7 microns. The dielectric substrate is photopolymer with relative permittivity ε = 2.4 and thickness h = 0.5 μm. The structure is located along the x and y directions with period p = 10 microns. The incident wave is perpendicular to x–y plane with Ex polarization.
Mathematical modeling for numerical investigation of the influence of geometric dimensions of the nanostructure on the response of THz radiation induced by plasmons is carried out. With increasing length L of the nanotape resonance (f = 1.68 THz) is rapidly changing to lower THz frequencies.
From the modelling and simulation results it follows that the studied periodic layered graphene and dielectric nanostructures can be used for the creation of wide–band THz–band filters of planar design, controlled by electric field, and quickly tunable with small changes in the energy level Fermi of graphene.
Investigation was carried out at expense of grant of Russian Science Foundation (project No. 18-79-10109).
