Most of the current graphene plasmonic researches are based on the substrates with isotropic dielectric constant such as silicon.In this work,we investigate optical properties of graphene nanoribbon arrays placed on a...Most of the current graphene plasmonic researches are based on the substrates with isotropic dielectric constant such as silicon.In this work,we investigate optical properties of graphene nanoribbon arrays placed on a uniaxially anisotropic substrate,where the anisotropy provides an additional freedom to tune the behaviors of graphene plasmons,and its effect can be described by a simple effective formula.In practice,the substrates of semi-infinite and finite thickness are discussed by using both the formula and full wave simulations.Particularly,the dielectric constants ε|| and ε⊥ approaching zero are intensively studied,which show different impacts on the transverse magnetic(TM) surface modes.In reality,the hexagonal boron nitride(hBN) can be chosen as the anisotropic substrate,which is also a hyperbolic material in nature.展开更多
Topological edge states have an important role in optical modulation with potential applications in wavelength division multiplexers(WDMs).In this paper,2D photonic crystals(PCs)with different rotation angles are comb...Topological edge states have an important role in optical modulation with potential applications in wavelength division multiplexers(WDMs).In this paper,2D photonic crystals(PCs)with different rotation angles are combined to generate topological edge states.We reveal the relationship between the edge states and the rotation parameters of PCs,and further propose a WDM to realize the application of adjustable beams.Our findings successfully reveal the channel selectivity for optical transmission and provide a flexible way to promote the development of topological photonic devices.展开更多
Many works on topological insulators have focused on periodic lattice systems,where short-and long-range order is considered.Here we construct a two-dimensional amorphous photonic crystal with short-range order and a ...Many works on topological insulators have focused on periodic lattice systems,where short-and long-range order is considered.Here we construct a two-dimensional amorphous photonic crystal with short-range order and a controllable level of long-range order and experimentally investigate the transport of topological edge states in this amorphous system.We demonstrate that topology properties remain constant with unidirectional edge state propagation,immune to specific disorder strength.The partition phenomena of edge states are also observed at the intersection of four topological channels in microwave experiments.This proposed amorphous configuration provides new opportunities to explore the relationship between short-range order and topology and may alleviate the fabrication difficulties of topological optical devices for practical applications.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11604382 and 11574140)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20160236).
文摘Most of the current graphene plasmonic researches are based on the substrates with isotropic dielectric constant such as silicon.In this work,we investigate optical properties of graphene nanoribbon arrays placed on a uniaxially anisotropic substrate,where the anisotropy provides an additional freedom to tune the behaviors of graphene plasmons,and its effect can be described by a simple effective formula.In practice,the substrates of semi-infinite and finite thickness are discussed by using both the formula and full wave simulations.Particularly,the dielectric constants ε|| and ε⊥ approaching zero are intensively studied,which show different impacts on the transverse magnetic(TM) surface modes.In reality,the hexagonal boron nitride(hBN) can be chosen as the anisotropic substrate,which is also a hyperbolic material in nature.
基金National Key Research and Development Program of China(2022YFE0122300)National Natural Science Foundation of China(11811530052,12004425,1211101294,62105126)+2 种基金State Key Laboratory of Millimeter Waves(K202105,K202238)Intergovernmental Science and Technology Regular Meeting Exchange Project of Ministry of Science and Technology of China(CB02-20)Natural Science Foundation of Jiangsu Province(BK20200630)。
文摘Topological edge states have an important role in optical modulation with potential applications in wavelength division multiplexers(WDMs).In this paper,2D photonic crystals(PCs)with different rotation angles are combined to generate topological edge states.We reveal the relationship between the edge states and the rotation parameters of PCs,and further propose a WDM to realize the application of adjustable beams.Our findings successfully reveal the channel selectivity for optical transmission and provide a flexible way to promote the development of topological photonic devices.
基金supported by the Key Academic Discipline Project of China University of Mining and Technology(Grant No.2022WLXK06)the National Natural Science Foundation of China(Grant Nos.11874274,12004425,and 12274315)+3 种基金the Natural Science Foundation of Jiangsu Province(Grant No.BK20200630)the Qing Lan Projecta Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Basic Research Program of Xuzhou(Grant No.KC22016)。
文摘Many works on topological insulators have focused on periodic lattice systems,where short-and long-range order is considered.Here we construct a two-dimensional amorphous photonic crystal with short-range order and a controllable level of long-range order and experimentally investigate the transport of topological edge states in this amorphous system.We demonstrate that topology properties remain constant with unidirectional edge state propagation,immune to specific disorder strength.The partition phenomena of edge states are also observed at the intersection of four topological channels in microwave experiments.This proposed amorphous configuration provides new opportunities to explore the relationship between short-range order and topology and may alleviate the fabrication difficulties of topological optical devices for practical applications.
