超表面由于具备独特的电磁响应特性,在微波、太赫兹以及光学领域的应用十分广泛.在电磁超表面中构建连续域束缚态(bound states in the continuum,BIC)模式谐振可以产生尖锐的谐振透射峰,因此BIC被广泛用于设计具有高品质因子谐振的超表...超表面由于具备独特的电磁响应特性,在微波、太赫兹以及光学领域的应用十分广泛.在电磁超表面中构建连续域束缚态(bound states in the continuum,BIC)模式谐振可以产生尖锐的谐振透射峰,因此BIC被广泛用于设计具有高品质因子谐振的超表面.本文实验研究了一种支持准BIC(quasi-BIC,q-BIC)谐振的新型金属太赫兹超表面,通过设计两组金属开口谐振环(split ring resonators,SRRs)的结构参数来调节各自主导的谐振的工作频率,使不同模式谐振之间产生耦合,形成q-BIC模式谐振.并利用电磁场分布及其散射功率的多极分解的计算结果证明了不同模式的共振机制.在入射电磁波分别沿x,y偏振时,通过Jaynes-Cummings模型计算了两模式之间的归一化耦合强度比,分别为0.54%(x偏振)与4.42%(y偏振),解释了不同谐振模式的工作频率随SRRs器件结构参数改变而变化的规律.展开更多
We conduct a theoretical analysis of the massive and tunable Goos–Hänchen(GH) shift on a polar crystal covered with periodical black phosphorus(BP)-patches in the THz range. The surface plasmon phonon polaritons...We conduct a theoretical analysis of the massive and tunable Goos–Hänchen(GH) shift on a polar crystal covered with periodical black phosphorus(BP)-patches in the THz range. The surface plasmon phonon polaritons(SPPPs), which are coupled by the surface phonon polaritons(SPh Ps) and surface plasmon polaritons(SPPs), can greatly increase GH shifts.Based on the in-plane anisotropy of BP, two typical metasurface models are designed and investigated. An enormous GH shift of about-7565.58 λ_(0) is achieved by adjusting the physical parameters of the BP-patches. In the designed metasurface structure, the maximum sensitivity accompanying large GH shifts can reach about 6.43 × 10^(8) λ_(0)/RIU, which is extremely sensitive to the size, carrier density, and layer number of BP. Compared with a traditional surface plasmon resonance sensor, the sensitivity is increased by at least two orders of magnitude. We believe that investigating metasurface-based SPPPs sensors could lead to high-sensitivity biochemical detection applications.展开更多
A phoxonic crystal waveguide with the glide symmetry is designed,in which both electromagnetic and elastic waves can propagate along the glide plane at the same time.Due to the glide symmetry,the bands of the phoxonic...A phoxonic crystal waveguide with the glide symmetry is designed,in which both electromagnetic and elastic waves can propagate along the glide plane at the same time.Due to the glide symmetry,the bands of the phoxonic crystal super-cell degenerate in pairs at the boundary of the Brillouin zone.This is the so-called band-sticking effect and it causes the appearance of gapless guided-modes.By adjusting the magnitude of the glide dislocation the edge bandgaps,the bandgap of the guided-modes at the boundary of the Brillouin zone,can be further adjusted.The photonic and phononic guided-modes can then possess only one mode for a certain frequency with relatively low group velocities,achieving single-mode guided-bands with relatively flat dispersion relationship.In addition,there exists acousto-optic interaction in the cavity constructed by the glide plane.The proposed waveguide has potential applications in the design of novel optomechanical devices.展开更多
The influence of the longitudinal acceleration and the angular acceleration of detecting target based on vortex electromagnetic waves in keyhole space are analyzed.The spectrum spreads of different orbital angular mom...The influence of the longitudinal acceleration and the angular acceleration of detecting target based on vortex electromagnetic waves in keyhole space are analyzed.The spectrum spreads of different orbital angular momentum(OAM)modes in different non-line-of-sight situations are simulated.The errors of target accelerations in detection are calculated and compared based on the OAM spectra spreading by using two combinations of composite OAM modes in the keyhole space.According to the research,the effects about spectrum spreads of higher OAM modes are more obvious.The error in detection is mainly affected by OAM spectrum spreading,which can be reduced by reasonably using different combinations of OAM modes in different practical situations.The above results provide a reference idea for investigating keyhole effect when vortex electromagnetic wave is used to detect accelerations.展开更多
The supercritical CO_(2)cOoled Lithium-Lead(COOL)blanket has been designed as one advanced blanket candidate for the Chinese Fusion Engineering Test Reactor(CFETR).This work focuses on the electromagnetic(EM)loads(Max...The supercritical CO_(2)cOoled Lithium-Lead(COOL)blanket has been designed as one advanced blanket candidate for the Chinese Fusion Engineering Test Reactor(CFETR).This work focuses on the electromagnetic(EM)loads(Maxwell force and Lorentz force)acting on the COOL blanket,which are important mechanical loads in further structural analysis of the COOL blanket.A 3D electromagnetic analysis is performed using the ANSYS finite element method to obtain EM loads on the COOL blanket in this study.At first,the magnetic scalar potential(MSP)method is used to obtain the magnetic field and the Maxwell force on the COOL blanket.Then,the magnetic vector potential(MVP)method is performed during a plasma disruption event to get the eddy current distribution.At last,a multi-step method is adopted for the calculation of the Lorentz force and the torque.The maximum Lorentz forces of inboard and outboard blanket structural components are 5624 kN and 2360 kN respectively.展开更多
文摘超表面由于具备独特的电磁响应特性,在微波、太赫兹以及光学领域的应用十分广泛.在电磁超表面中构建连续域束缚态(bound states in the continuum,BIC)模式谐振可以产生尖锐的谐振透射峰,因此BIC被广泛用于设计具有高品质因子谐振的超表面.本文实验研究了一种支持准BIC(quasi-BIC,q-BIC)谐振的新型金属太赫兹超表面,通过设计两组金属开口谐振环(split ring resonators,SRRs)的结构参数来调节各自主导的谐振的工作频率,使不同模式谐振之间产生耦合,形成q-BIC模式谐振.并利用电磁场分布及其散射功率的多极分解的计算结果证明了不同模式的共振机制.在入射电磁波分别沿x,y偏振时,通过Jaynes-Cummings模型计算了两模式之间的归一化耦合强度比,分别为0.54%(x偏振)与4.42%(y偏振),解释了不同谐振模式的工作频率随SRRs器件结构参数改变而变化的规律.
基金Project supported by the Natural Science Foundation of Heilongjiang Province of China (Grant No.LH2020A014)the Graduate Students' Research Innovation Project of Harbin Normal University (Grant No.HSDSSCX2022-47)。
文摘We conduct a theoretical analysis of the massive and tunable Goos–Hänchen(GH) shift on a polar crystal covered with periodical black phosphorus(BP)-patches in the THz range. The surface plasmon phonon polaritons(SPPPs), which are coupled by the surface phonon polaritons(SPh Ps) and surface plasmon polaritons(SPPs), can greatly increase GH shifts.Based on the in-plane anisotropy of BP, two typical metasurface models are designed and investigated. An enormous GH shift of about-7565.58 λ_(0) is achieved by adjusting the physical parameters of the BP-patches. In the designed metasurface structure, the maximum sensitivity accompanying large GH shifts can reach about 6.43 × 10^(8) λ_(0)/RIU, which is extremely sensitive to the size, carrier density, and layer number of BP. Compared with a traditional surface plasmon resonance sensor, the sensitivity is increased by at least two orders of magnitude. We believe that investigating metasurface-based SPPPs sensors could lead to high-sensitivity biochemical detection applications.
基金Project supported by the National Natural Science Foundation of China(Grant No.12064025)the Natural Science Foundation of Jiangxi Province,China(Grant No.20212ACB202006)+1 种基金the Major Discipline Academic and Technical Leaders Training Program of Jiangxi Province,China(Grant No.20204BCJ22012)the Open Project of the Key Laboratory of Radar Imaging and Microwave Photonic Technology of the Education Ministry of China.
文摘A phoxonic crystal waveguide with the glide symmetry is designed,in which both electromagnetic and elastic waves can propagate along the glide plane at the same time.Due to the glide symmetry,the bands of the phoxonic crystal super-cell degenerate in pairs at the boundary of the Brillouin zone.This is the so-called band-sticking effect and it causes the appearance of gapless guided-modes.By adjusting the magnitude of the glide dislocation the edge bandgaps,the bandgap of the guided-modes at the boundary of the Brillouin zone,can be further adjusted.The photonic and phononic guided-modes can then possess only one mode for a certain frequency with relatively low group velocities,achieving single-mode guided-bands with relatively flat dispersion relationship.In addition,there exists acousto-optic interaction in the cavity constructed by the glide plane.The proposed waveguide has potential applications in the design of novel optomechanical devices.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11804073 and 61775050).
文摘The influence of the longitudinal acceleration and the angular acceleration of detecting target based on vortex electromagnetic waves in keyhole space are analyzed.The spectrum spreads of different orbital angular momentum(OAM)modes in different non-line-of-sight situations are simulated.The errors of target accelerations in detection are calculated and compared based on the OAM spectra spreading by using two combinations of composite OAM modes in the keyhole space.According to the research,the effects about spectrum spreads of higher OAM modes are more obvious.The error in detection is mainly affected by OAM spectrum spreading,which can be reduced by reasonably using different combinations of OAM modes in different practical situations.The above results provide a reference idea for investigating keyhole effect when vortex electromagnetic wave is used to detect accelerations.
基金supported by the Comprehensive Research Facility for Fusion Technology(CRAFT)Program of China(No.2018-000052-73-01-001228)National Natural Science Foundation of China(No.12205330)。
文摘The supercritical CO_(2)cOoled Lithium-Lead(COOL)blanket has been designed as one advanced blanket candidate for the Chinese Fusion Engineering Test Reactor(CFETR).This work focuses on the electromagnetic(EM)loads(Maxwell force and Lorentz force)acting on the COOL blanket,which are important mechanical loads in further structural analysis of the COOL blanket.A 3D electromagnetic analysis is performed using the ANSYS finite element method to obtain EM loads on the COOL blanket in this study.At first,the magnetic scalar potential(MSP)method is used to obtain the magnetic field and the Maxwell force on the COOL blanket.Then,the magnetic vector potential(MVP)method is performed during a plasma disruption event to get the eddy current distribution.At last,a multi-step method is adopted for the calculation of the Lorentz force and the torque.The maximum Lorentz forces of inboard and outboard blanket structural components are 5624 kN and 2360 kN respectively.