Structure Design And Properties Of Subwavelength Transmission Based On Graphene

Plasmons,the collective oscillations of electrons in conducting materials,possess a number of appealing properties for photonic technologies along with the development of nanophotonics.Plasmons can break diffraction limit and successfully confine the incident light distance above the interface less than the corresponding free-space wavelength.Thus it can greatly reduce the size of optical devices.Since this technique was proposed,it has been a potential candidate to guide the opto-electronic integration.Graphene,a novel 2-dimensional material,has many application potential in nanophotonics and integrated optics.Recently,its excellent optical properties e.g.tunability and subwavelength propagation have attract many scientific staffs.In many published papers,graphene and graphene-based nanostructures have many applications in modulation and subwavelength propagation.Also,it has huge application potential in super resolution imagination,biosensing and nano energy technology.In this paper,the light absorption properties of graphene which is based on light-matter interaction with electromagnetic mechanism is studied.The optical properties of graphene is mainly obtained by Matlab and COMSOL.Meanwhile,a graphene-based hybrid plasmonic modulator combining graphene and conventional plasmonic waveguide which can achieve subwavelength modulation in near-infrared communication range is proposed.Also,the performance of this modulator is studied and optimized.Furthermore,the terahertz optical properties of graphene-hexagonal boron nitride heterostructure in different structures is studied.In conclusion,we introduce our work in five parts which are shown as follow:1.The conventional optical devices and modulators are studied on the basis of relevant scientific information.The properties of graphene in the application of conventional optoelectronic modulators have been studied.Also,the plasmonic waveguide is discussed.2.The detailed optoelectronic properties of graphene in near-infrared range are derived by Kubo formula.Also,conventional graphene-based modulators are discussed.A method to evaluate and optimize the performance of conventional graphene based modulators is proposed.The calculation result shows that this method can fit the experimental result.And the properties of surface plasmon polaritons above the metal surface is studied by utilizing classical electromagnetic theory.The performance of the hybrid plasmonic waveguide is also evaluated.3.Study the plasmons mode of graphene and its optical response in near-infrared range utilizing random phase approximation method.Combining graphene and hybrid plasmonic waveguide,a graphene-based hybrid plasmonic modulator which can achieve subwavelength modulation is proposed.The modulation depth of this modulator is approximately 0.6d B/?m under design conditions.4.The optical response of graphene-hexagonal boron nitride heterostructure is studied.The surface plasmon polaritons-hyperbolic phonon polaritons coupling modes generated by near field excitation is investigated.The tunability mechanism of this special metamaterial is studied in this paper.Subsequently,the effects of graphene's Fermi level and h-BN's thickness are also studied.Also,two different coupling system are designed to investigate the different modes dominated coupling properties.5.Relevant applications of graphene and plasmons are concluded e.g.graphene plasmons terahertz antennas,plasmonics in hyperdoped semiconductors in nano energy technology and molecular detection.The development of this field is discussed.