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floquet metamaterials

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eLight 2022年第1期2卷 99-111页

作者： Shixiong Yin Emanuele Galiffi Andrea Alù Photonics Initiative Advanced Science Research CenterThe City University of New York85 St.Nicholas TerraceNew York 10031USA Department of Electrical Engineering City CollegeThe City University of New York160 Convent AvenueNew York 10031USA Physics Program The Graduate CenterThe City University of New York365 Fifth AvenueNew York 10016USA

Recent progress in nanophotonics and material science has inspired a strong interest in optically-induced material dynamics,opening new research directions in the distinct fields of floquet matter and time metamaterials.floquet phenomena are historically rooted in the condensed matter community,as they exploit periodic temporal drives to unveil novel phases of matter,unavailable in systems at equilibrium.In parallel,the field of metamaterials has been offering a platform for exotic wave phenomena based on tailored materials at the nanoscale,recently enhanced by incorporating time variations and switching as new degrees of freedom.In this Perspective,we connect these research areas and describe the exciting opportunities emerging from their synergy,hinging on giant wave-matter interactions enabled by metamaterials and on the exotic wave dynamics enabled by floquet and parametric phenomena.We envision floquet metamaterials in which nontrivial modulation dynamics,and their interplay with tailored material dispersion and nontrivial material properties such as anisotropy,non-Hermiticity and nonreciprocity,introduce a plethora of novel opportunities for wave manipulation and control.

关键词： floquet Metamaterials Time Switching

floquet spectrum and optical behaviors in dynamic Su–Schrieffer–Heeger modeled waveguide array

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Chinese Optics Letters 2021年第4期19卷 71-76页

作者：余晔宋一雯陈焘王怀强庄松林程庆庆 School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China National Laboratory of Solid State Microstructures School of PhysicsNanjing UniversityNanjing 210093China

floquet topological insulators(FTIs) have been used to study the topological features of a dynamic quantum system within the band structure. However, it is difficult to directly observe the dynamic modulation of band structures in FTIs. Here, we implement the dynamic Su–Schrieffer–Heeger model in periodically curved waveguides to explore new behaviors in FTIs using light field evolutions. Changing the driving frequency produces near-field evolutions of light in the high-frequency curved waveguide array that are equivalent to the behaviors in straight arrays. Furthermore, at modest driving frequencies,the field evolutions in the system show boundary propagation, which are related to topological edge modes. Finally, we believe curved waveguides enable profound possibilities for the further development of floquet engineering in periodically driven systems, which ranges from condensed matter physics to photonics.

关键词： topological photonics insulator waveguide array floquet

Identifying anomalous floquet edge modes via bulk-edge correspondence

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Chinese Physics B 2020年第4期29卷 434-438页

作者：王寰宇刘伍明 Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

floquet engineering appears as a new protocol for designing topological states of matter,and features anomalous edge modes pinned at quasi-energy π/T with vanished topological index.We propose how to predict the anomalous edge modes via the bulk Hamiltonian in frequency space,and use Zak phase to quantitatively index the topological properties.The above methods are clarified by the example of time periodic Kitaev chain with chemical potential of harmonic driving and pulse driving,and topological phase transitions are manifested at different driving frequencies.

关键词： floquet energineering bulk-edge correspondence Zak phase

floquet Eigenvectors Theory of Pulsed Bias Phase and Quadrature Harmonic Oscillators

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Circuits and Systems 2012年第1期3卷 72-81页

作者： Fabrizio Palma Stefano Perticaroli 不详

The paper presents an analytical derivation of floquet eigenvalues and eigenvectors for a class of harmonic phase and quadrature oscillators. The derivation refers in particular to systems modeled by two parallel RLC resonators with pulsed energy restoring. Pulsed energy restoring is obtained through parallel current generators with an impulsive characteristic triggered by the resonators voltages. In performing calculation the initial hypothesis of the existence of stable oscillation is only made, then it is verified when both oscillation amplitude and eigenvalues/eigenvectors are deduced from symmetry conditions on oscillator space state. A detailed determination of the first eigenvector is obtained. Remaining eigenvectors are hence calculated with realistic approximations. Since floquet eigenvectors are acknowledged to give the correct decomposition of noise perturbations superimposed to the oscillator space state along its limit cycle, an analytical and compact model of their behavior highlights the unique phase noise properties of this class of oscillators.

关键词： floquet Eigenvectors Noise Decomposition Phase and Quadrature Oscillators Pulsed Bias Oscillator Oscillator Phase Noise

floquet Theory in Electron-Helium Scattering in a Nd:YAG Laser Field

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Optics and Photonics Journal 2013年第8期3卷 18-27页

作者： Abdelkader Makhoute Hicham Agueny Soumia Chqondi 1UFR de Physique du Rayonnement et des Interactions Laser-Matière Faculté des Sciences Université Moulay Ismail Meknès Morocco 2Laboratoire de Chimie Physique-Matière et Rayonnement Université Pierre et Marie Curie Paris France 1UFR de Physique du Rayonnement et des Interactions Laser-Matière Faculté des Sciences Université Moulay Ismail Meknès Morocco 2The Abdus Salam International Centre for Theoretical Physics Trieste Italy

The dynamics of laser-assisted elastic collisions in helium is studied. The formalism which will be developed to describe such laser-assisted collisions, treats the laser-projectile interaction to all orders, while the electron-helium interaction is treated within the first Born-approximation. Detailed calculations are performed for the elastic scattering of 50 eV electrons by helium accompanied by the transfer of photons. The numerical results show that the good physical interpretation of relevant processes needs to consider the maximum of atomic states.

关键词： Laser-Assisted Elastic Collisions Born-Approximation floquet Theory Multiphoton Transitions Low-Lying High-Lying Differential Cross Section

含时变切换的广义时滞反馈控制镇定多旋转周期轨线

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物理学报 2023年第8期72卷 84-92页

作者：曾尖尖鲍丽娟南昌航空大学数学与信息科学学院南昌330063

基于时变切换策略,给出了原广义时滞反馈控制的一种改进方案,即含时变切换的广义时滞反馈控制.含时变切换的广义时滞反馈控制只在特定时段上对受控系统施加控制,而在其他时段上不施加控制,这不同于原广义时滞反馈控制具有的恒定控制.通... 详细信息

基于时变切换策略,给出了原广义时滞反馈控制的一种改进方案,即含时变切换的广义时滞反馈控制.含时变切换的广义时滞反馈控制只在特定时段上对受控系统施加控制,而在其他时段上不施加控制,这不同于原广义时滞反馈控制具有的恒定控制.通过实例分析,研究了含时变切换的广义时滞反馈控制在镇定不稳定多旋转周期轨线中的具体性能.通过计算受控周期轨线的最大floquet乘数,得到了受控多旋转周期轨线的稳定区域随切换频率变化的关系图.结果表明,随着切换频率的增大,受控多旋转周期轨线的稳定区域呈现非平滑变化.特别地,当选择适当的切换频率时,含时变切换的广义时滞反馈控制的稳定区域显著大于原广义时滞反馈控制的稳定区域.

关键词：混沌控制时滞反馈周期轨线 floquet 乘数

Anharmonic Potentials Analysis through the floquet Representation

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Journal of Applied Mathematics and Physics 2020年第1期8卷 184-195页

作者： Mohammed Janati Idrissi Abdelaziz Fedoul Salaheddine Sayouri Ibrahim Amila Laboratory of Theoretical and Applied Physics Faculty of Sciences Dhar Al Mahraz University of Sidi Mohamed Ben Abdellah Fez Morocco

We propose an approach based on floquet theorem combined with the resonating averages method (RAM), to solve the time-dependent Schrödinger equation with a time-periodic Hamiltonian. This approach provides an alternative way to determine directly the evolution operator, and then we deduct the wave functions and the corresponding quasi-energies, of quantum systems. An application is operated for the driven cubic or/and quatric anharmonic as well as for the Morse potential. Comparisons of our results with those of other authors are discussed, and numerical evaluations are performed, to determine the dissociation energy of (HCl) and (CO) molecules.

关键词： floquet Theorem Resonating Averages Anharmonic Potential

Derivation of floquet Eigenvectors Displacement for Optimal Design of LC Tank Pulsed Bias Oscillators

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Circuits and Systems 2011年第4期2卷 311-319页

作者： Stefano Perticaroli Nikend Luli Fabrizio Palma 不详

The paper presents an approximated and compact derivation of the mutual displacement of floquet eigenvectors in a class of LC tank oscillators with time varying bias. In particular it refers to parallel tank oscillators of which the energy restoring can be modeled through a train of current pulses. Since floquet eigenvectors are acknowledged to give a correct decomposition of noise perturbations along the stable orbit in oscillator's space state, an analytical and compact model of their displacement can provide useful criteria for designers. The goal is to show, in a simplified case, the achievement of oscillators design oriented by eigenvectors. To this aim, minimization conditions of the effect of stationary and time varying noise as well as the contribution of jitter noise introduced by driving electronics are deduced from analytical expression of eigenvectors displacement.

关键词： floquet Eigenvectors Noise Decomposition Pulsed Bias Oscillator Oscillator Phase Noise

Synthesis and Optimization of Almost Periodic Antennas Using floquet Modal Analysis and MoM-GEC Method

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Journal of Electromagnetic Analysis and Applications 2019年第1期11卷 1-16页

作者： Nader Ben Latifa Taoufik Aguili Laboratory of the Communication Systems National Engineering School of Tunis Le Blvedere Tunis Tunisia

This paper presented a new floquet analysis used to calculate the radiation for 1-D and 2-D coupled periodic antenna systems. In this way, an accurate evaluation of mutual coupling can be proven by using a new mutual interaction expression that was based on Fourier analysis. Then, this work indicated how floquet analysis can be used to study a finite array with uniform amplitude and linear phase distribution in both x and y directions. To modelize the proposed structures, two formulations were given in a spectral and spatial domain, where the Moment (MoM) method combined with a generalized equivalent circuit (GEC) method was applied. Radiation pattern of coupled periodic antenna was shown by varying many parameters, such as frequencies, distance and floquet states. The 3-D radiation beam of the coupled antenna array was analyzed and compared in several steering angles θs and coupling values dx. The simulation of this structure demonstrated that directivity decreased at higher coupling values. The secondary lobs in the antenna radiation pattern affected the main lobe gain by energy dispersal and considerable increasing of side lobe level (SLL) may be achieved. Therefore, the sweeping of the radiation beam in several steering directions affected the electromagnetic performance of the antenna system: the directivity at the steering angle θs = π⁄3 was more damaged and had 19.99 dB while the second at θs = 0 had about 35.11 dB. This parametric study of coupled structure used to concept smart periodic antenna with sweeping radiation beam.

关键词： Periodic Antennas floquet Theory Moment Method GEC Method