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Journal articles on the topic 'Matter wave guiding'

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Author: Grafiati

Published: 10 December 2022

Last updated: 28 January 2023

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1

Riyopoulos, Spilios. "Guiding-centre orbits for particles in cross-field devices." Journal of Plasma Physics 46, no. 3 (December 1991): 473–85. http://dx.doi.org/10.1017/s0022377800016263.

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The motion of a particle driven by a slow RF wave inside crossed electrostatic and magnetostatic fields is examined. A time-scale separation exists in the synchronous frame, moving at the slow-wave phase velocity, where all fields appear static in time and the cyclotron motion is much faster than the guidingcentre drift. The averaging of the periodic gyromotion is performed systematically with canonical transformations up to second order in the smallwave amplitude. The first-order guiding-centre drift follows the equipotential surfaces of the transformed electric field. The second-order effects, due to the field-line curvature, and/or the nonlinear variation in the wave phase velocity, cause departures from the parapotential flow. The topology of the trajectories depends on the departure of the drift velocity from synchronism with the wave. Various flow topologies corresponding to different values of the control parameters are examined.

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2

MIRZANEJHAD, SAEED, BEHROUZ MARAGHECHI, FARSHAD SOHBATZADEH, and IMAN KAMEL-JAHROMI. "Space-charge waves in a relativistic electron beam with ion-channel guiding." Journal of Plasma Physics 77, no. 3 (November 5, 2010): 419–29. http://dx.doi.org/10.1017/s0022377810000632.

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AbstractSpace-charge waves in a relativistic electron beam that completely fills a cylindrical metallic waveguide and is guided by an ion channel are analyzed numerically. Equilibrium consists of a uniform and rigid rotation without betatron oscillations. Using cold fluid equations a differential equation and boundary conditions are derived that constitute an eigenvalue problem. This eigenvalue problem is solved, numerically, with the finite difference scheme using shooting method. Dispersion characteristics and electrostatic potential structures of azimuthally symmetric and nonsymmetric space-charge waves are studied. Perfect agreement with analytical results at asymptotic limit of zero axial velocity is found. It was found that relativistic effects modify the dispersion characteristics of the space-charge waves considerably and can concentrate the electric field energy of the wave into a thin and small shell around the axis.

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3

Deleniv, A. N. "Full-wave analysis of coupled strip-slot guiding structures." IEEE Transactions on Microwave Theory and Techniques 53, no. 6 (June 2005): 1904–12. http://dx.doi.org/10.1109/tmtt.2005.848087.

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4

VARMA, RAM K. "Macro-quantization of the guiding centre motion of charged particles in a magnetic field." Journal of Plasma Physics 79, no. 2 (October 9, 2012): 197–213. http://dx.doi.org/10.1017/s0022377812000840.

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AbstractThis review describes the results of investigations on charged particle dynamics in a magnetic field carried out over a number of years. The studies have unravelled the existence of some very surprising and unusual phenomena. Though existing on the macro-scale, they are found to be of quantum origin, and are thereby not covered by the Lorentz equation, which has been regarded conventionally as the descriptor of electrodynamic phenomena on the macro-scale. These novel phenomena have been found to be attributed to the ‘quantum modulation’ of the de Broglie wave along the magnetic field. This is brought about through the scattering-induced transition across Landau levels, leading to the modulation of the plane wave state along the field as a result of the entanglement between the parallel and perpendicular degrees of freedom. These findings were motivated by the predictions of a formalism developed by the author and include such unusual phenomena as (i) macro-scale matter wave interference effects and (ii) the detection of curl-free vector potential also on the macro-scale, both attributed to quantum modulation which is a matter wave on the macro-scale. The formalism is thus described as ‘macro-quantization of guiding centre motion’.

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5

MEHDIAN, H., and S. JAFARI. "A comparison between electron orbits for both an axial magnetic field and an ion-channel guiding in a FEL with an electromagnetic wave wiggler." Journal of Plasma Physics 74, no. 2 (April 2008): 187–96. http://dx.doi.org/10.1017/s0022377807006873.

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AbstractThe operation of a free-electron laser (FEL) with electromagnetic wave wiggler in the presence of an ion-channel guiding as well as an axial guide magnetic field is considered and compared. Theoretical studies of electron trajectories and dispersion relations in a combined ion electrostatic field as well as large-amplitude backward-propagating electromagnetic waves are analyzed. The large-amplitude wave acts like a magnetostatic wiggler in a FEL. The results of a numerical study are presented and discussed. It is shown that in the wiggler pumped ion-channel free-electron laser (WPIC-FEL), electron orbits and dispersion relation are time-dependent, and over time, electron orbits while oscillating bear a periodic motion.

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6

Rouhani, M. H., and B. Maraghechi. "Wave-mode dispersions in a relativistic electron beam with ion-channel guiding." Physics of Plasmas 13, no. 8 (August 2006): 083101. http://dx.doi.org/10.1063/1.2245563.

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7

Balakin, Alexander B. "The extended Einstein–Maxwell-aether-axion model: Exact solutions for axionically controlled pp-wave aether modes." Modern Physics Letters A 33, no. 09 (March 21, 2018): 1850050. http://dx.doi.org/10.1142/s0217732318500505.

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The extended Einstein–Maxwell-aether-axion model describes internal interactions inside the system, which contains gravitational, electromagnetic fields, the dynamic unit vector field describing the velocity of an aether, and the pseudoscalar field associated with the axionic dark matter. The specific feature of this model is that the axion field controls the dynamics of the aether through the guiding functions incorporated into Jacobson’s constitutive tensor. Depending on the state of the axion field, these guiding functions can control and switch on or switch off the influence of acceleration, shear, vorticity and expansion of the aether flow on the state of physical system as a whole. We obtain new exact solutions, which possess the pp-wave symmetry, and indicate them by the term pp-wave aether modes in contrast to the pure pp-waves, which cannot propagate in this field conglomerate. These exact solutions describe a specific dynamic state of the pseudoscalar field, which corresponds to one of the minima of the axion potential and switches off the influence of shear and expansion of the aether flow; the model does not impose restrictions on Jacobson’s coupling constants and on the axion mass. Properties of these new exact solutions are discussed.

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8

Bhatia, Aman, Keshav Walia, and Arvinder Singh. "Laguerre–Gaussian laser beam guiding and its second harmonics in plasma having density ramp." Physics of Plasmas 29, no. 9 (September 2022): 092107. http://dx.doi.org/10.1063/5.0103924.

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This paper presents the optical guiding of a laser beam in plasma by using a preformed plasma channel. The density ramp in plasma density due to the plasma pressure has also been considered. The effect of ponderomotive force has been taken into account which originates due to the intensity gradient present in the laser beam. This force produces a plasma gradient by expelling plasma electrons from a high-field to a low-field region, providing heavy ions remain immobile. Plasma oscillations result from a gradient in plasma density that excites an electron plasma wave. The equation governing the plasma wave excitation has been found by using linear perturbation theory. An in-phase mixing of an incident laser beam with this plasma wave generates its second harmonics. Laguerre–Gaussian laser profile has been used for harmonic production. Moment theory has been used to obtain a differential equation for beam waist, which has been solved numerically by Runge–Kutta's fourth-order method. The effect of different modes of Laguerre–Gaussian profile, beam intensity, plasma density, channel depth, and slope of density ramp has been explored.

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9

WARENGHEM, M., J. F. HENNINOT, and G. ABBATE. "FROM BULK JANOSSY EFFECT TO NONLINEAR SELF WAVE-GUIDING OR SPATIAL SOLUTION IN DYE-DOPED LIQUID CRYSTALS." Journal of Nonlinear Optical Physics & Materials 08, no. 03 (September 1999): 341–60. http://dx.doi.org/10.1142/s0218863599000242.

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The pure liquid crystalline state of matter is known for its large optical nonlinearity. The effect has been widely studied in thin film as the beam crosses it. Few studies have been done for a geometry in which the light interacts with the matter on a large volume. In this paper, we report the results we have obtained in this configuration (Bulk Optical Freederisckz Effect) and for dye-doped liquid crystals. In such mixtures, the nonlinear effect occurs at low input powers and is called the Janossy effect. Besides similar behaviors which occur in the Bulk Freederisckz Effect, it is reported in this paper a beam behavior, namely a self wave-guiding or "spatial soliton," which is probably more specific to the bulk Janossy Effect. This self created wave-guide is assigned to be a consequence of the dye absorption: the optically induced refractive index gradient is finely tuned by the additional anisotropic thermal contribution, allowing a quasi perfect optical coupling of the fiber source with the optically induced liquid crystal wave-guide.

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10

Ren, Guobin, Yandong Gong, Ping Shum, Xia Yu, and Juanjuan Hu. "Polarization Maintaining Air-Core Bandgap Fibers for Terahertz Wave Guiding." IEEE Journal of Quantum Electronics 45, no. 5 (May 2009): 506–13. http://dx.doi.org/10.1109/jqe.2009.2013099.

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11

Newton, M. I., G. McHale, and F. Martin. "Experimental study of Love wave devices with thick guiding layers." Sensors and Actuators A: Physical 109, no. 3 (January 2004): 180–85. http://dx.doi.org/10.1016/j.sna.2003.10.034.

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12

Li, Xiaoze, Wei Song, Weibing Tan, Ligang Zhang, Jiancang Su, Xiaoxin Zhu, Xianggang Hu, Zhiyuan Shen, Xu Liang, and Qi Ning. "Design of a high efficiency relativistic backward wave oscillator with low guiding magnetic field." Physics of Plasmas 23, no. 7 (July 2016): 073101. http://dx.doi.org/10.1063/1.4954903.

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13

Mehdian, H., A. Hasanbeigi, and S. Jafari. "Free-electron laser harmonic generation in an electromagnetic-wave wiggler and ion channel guiding." Physics of Plasmas 17, no. 2 (February 2010): 023112. http://dx.doi.org/10.1063/1.3313356.

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14

Soliman, E. A., G. A. E. Vandenbosch, E. Beyne, and R. P. Mertens. "Full-wave analysis of multiconductor multislot planar guiding structures in layered media." IEEE Transactions on Microwave Theory and Techniques 51, no. 3 (March 2003): 874–86. http://dx.doi.org/10.1109/tmtt.2003.808624.

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15

Aghamir, Farzin M., and Hamid Almasi. "Electromagnetic Wave Propagation in an Annular Electron Beam With Ion Channel Guiding." IEEE Transactions on Plasma Science 39, no. 9 (September 2011): 1800–1806. http://dx.doi.org/10.1109/tps.2011.2160294.

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16

Mehdian, H., A. Hasanbeigi, and S. Jafari. "Self-fields in a free-electron laser with electromagnetic-wave wiggler and ion-channel guiding." Physics of Plasmas 15, no. 12 (December 2008): 123101. http://dx.doi.org/10.1063/1.3033745.

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17

Rao, Lei, Dongxiao Yang, and Zhi Hong. "Guiding terahertz wave within a line defect of photonic crystal slab." Microwave and Optical Technology Letters 54, no. 12 (September 25, 2012): 2856–58. http://dx.doi.org/10.1002/mop.27203.

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18

Liu, Yang, Zongsheng Chen, Li Cheng, Ke Sun, and Jiaming Shi. "6 GHz electromagnetic wave guiding along a femtosecond laser plasma filament." Microwave and Optical Technology Letters 62, no. 3 (November 4, 2019): 1009–16. http://dx.doi.org/10.1002/mop.32140.

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19

Hayran, Zeki, Seyyed Ali Hassani Gangaraj, and Francesco Monticone. "Topologically protected broadband rerouting of propagating waves around complex objects." Nanophotonics 8, no. 8 (May 9, 2019): 1371–78. http://dx.doi.org/10.1515/nanoph-2019-0075.

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AbstractAchieving robust propagation and guiding of electromagnetic waves through complex and disordered structures is a major goal of modern photonics research, for both classical and quantum applications. Although the realization of backscattering-free and disorder-immune guided waves has recently become possible through various photonic schemes inspired by topological insulators in condensed matter physics, the interaction between such topologically protected guided waves and free-space propagating waves remains mostly unexplored, especially in the context of scattering systems. Here, we theoretically demonstrate that free-space propagating plane waves can be efficiently coupled into topological one-way surface waves, which can seamlessly flow around sharp corners and electrically large barriers and release their energy back into free space in the form of leaky-wave radiation. We exploit this physical mechanism to realize topologically protected wave-rerouting around an electrically large impenetrable object of complex shape, with transmission efficiency exceeding 90%, over a relatively broad bandwidth. The proposed topological wave-rerouting scheme is based on a stratified structure composed of a topologically nontrivial magnetized plasmonic material coated by a suitable isotropic layer. Our results may open a new avenue in the field of topological photonics and electromagnetics, for applications that require engineered interactions between guided waves and free-space propagating waves, including for complex beam-routing systems and advanced stealth technology. More generally, our work may pave the way for robust defect/damage-immune scattering and radiating systems.

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20

Li, Bao-li, Dan-ran Li, Jin-hui Chen, Zeng-yong Liu, Guang-hui Wang, Xu-ping Zhang, Fei Xu, and Yan-qing Lu. "Hollow core micro-fiber for optical wave guiding and microfluidic manipulation." Sensors and Actuators B: Chemical 262 (June 2018): 953–57. http://dx.doi.org/10.1016/j.snb.2018.02.084.

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21

Fissi, Lamia El, Jean-Michel Friedt, Frédéric Chérioux, and Sylvain Ballandras. "Amine functionalized SU-8 layer guiding Love mode surface acoustic wave." Sensors and Actuators B: Chemical 144, no. 1 (January 29, 2010): 23–26. http://dx.doi.org/10.1016/j.snb.2009.09.011.

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22

Raum, Michael. "Design of a 2.5 THz submillimeter wave laser with optical pump beam guiding." International Journal of Infrared and Millimeter Waves 16, no. 12 (December 1995): 2147–61. http://dx.doi.org/10.1007/bf02073416.

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23

Kumar, Punit, and Nisha Singh Rathore. "Laser beam guiding in partially stripped magnetized quantum plasma." Laser Physics 32, no. 1 (December 14, 2021): 016002. http://dx.doi.org/10.1088/1555-6611/ac3ee7.

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Abstract Relativistic and ponderomotive nonlinearities arising by the passage of a linearly polarized laser beam through a partially stripped magnetized quantum plasma are analyzed. The interaction formalism has been developed using the recently developed quantum hydrodynamic model. The effects associated with the Fermi pressure, quantum Bohm potential and electron spin have been incorporated. A nonparaxial, non-linear wave equation has been obtained by the use of source dependent expansion technique and spot size has been evaluated. The nonlinear relativistic self-focusing tends to focus the beam while the ponderomotive nonlinearity tends to defocus. The effect of magnetization and quantum effects on the spot size and the beam power have been studied.

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24

Guo, Xu, Ying Sun, Chen-Lei Liu, Lin Jing, Yuan-Tao Zhang, Xiao-Long Wang, and Igor Timoshkin. "The guiding effect of artificially injected gas bubble on the underwater pulsed spark discharge and its electrical and acoustic parameters after breakdown." Physics of Plasmas 29, no. 11 (November 2022): 113504. http://dx.doi.org/10.1063/5.0122080.

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The presence of a low density area is beneficial to the facilitation of the underwater pulsed spark discharge, which can be achieved by artificially injecting gas bubble in between the inter-electrode gap. The generation of intensive acoustic waves by such gas-bubble-guided spark discharges makes them promising underwater acoustic sources in multiple practical applications. This paper is aimed at comprehensive investigation of the guiding effect of the injected bubble on the pre-breakdown process of underwater pulsed spark discharges and potential correlations between their subsequent electrical and acoustic parameters with the purpose of optimizing the acoustic emission. The breakdown probability and the pre-breakdown delay were used to evaluate the general facilitation effect brought by the injected bubble. Experimental and numerical works have been conducted and allow observation on the dynamics of the injected bubble under the influence of the applied voltage. Different guiding modes of the injected bubble for plasma streamers' propagation have been observed regarding its relative position. The characteristics of the electrical properties of gas-bubble-guided spark discharges, including the plasma resistance and the plasma energy density, were analyzed by relating them with the breakdown voltage. The dependency of the acoustic wave amplitude and the acoustic efficiency on these electrical parameters was verified, which provides solid regulation principles for the optimization of the plasma-acoustic system for target practical applications.

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25

SERGEEV, A. M., M. LONTANO, A. V. KIM, V. B. GILDENBURG, M. D. CHERNOBROVTSEVA, V. I. POZDNYAKOVA, and I. A. SHERESHEVSKII. "Ionization-induced leaking-mode channeling of intense short laser pulses in gases." Laser and Particle Beams 17, no. 1 (January 1999): 129–38. http://dx.doi.org/10.1017/s0263034699171106.

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We demonstrate that short laser pulse self-guiding over distances of many Rayleigh lengths can be achieved in the absence of any focusing nonlinearity as a result of trapping of a leaking wave in a plasma channel produced by field-induced ionization in the saturation regime. A detailed computational study of the new self-guiding effect in both cases of comparatively long laser pulses, when the traditional approximation of the slowly varying complex amplitude is valid, and of high intense ultrashort laser pulses comprising only few field cycles have been performed.

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26

Madine, K. H., and D. J. Colquitt. "Dynamic Green’s functions in discrete flexural systems." Quarterly Journal of Mechanics and Applied Mathematics 74, no. 3 (August 1, 2021): 323–50. http://dx.doi.org/10.1093/qjmam/hbab006.

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Summary The article presents an analysis of the dynamic behaviour of discrete flexural systems composed of Euler–Bernoulli beams. The canonical object of study is the discrete Green’s function, from which information regarding the dynamic response of the lattice under point loading by forces and moments can be obtained. Special attention is devoted to the interaction between flexural and torsional waves in a square lattice of Euler–Bernoulli beams, which is shown to yield a range of novel effects, including extreme dynamic anisotropy, asymmetric wave propagation, wave-guiding, filtering and the ability to create localised defect modes, all without the need for additional resonant elements or interfaces. The analytical study is complimented by numerical computations and finite element simulations, both of which are used to illustrate the effects predicted. A general algorithm is provided for constructing Green’s functions as well as defect modes. This algorithm allows the tuning of the lattice to produce pass bands, band gaps, resonant modes, wave-guides and defect modes, over any desired frequency range.

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27

Teng, Y., T. Z. Liang, and J. Sun. "Generation of beating wave by multi-coaxial relativistic backward wave oscillator." Laser and Particle Beams 31, no. 4 (September 19, 2013): 703–14. http://dx.doi.org/10.1017/s0263034613000773.

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AbstractMulti-coaxial relativistic backward wave oscillator that generates the beating wave of high power microwave pulse driven by a single accelerator and a single guiding magnet system is presented. Making use of the coaxial annular cathodes that can synchronously produce three annular beams at one shot, the average power of 5.88 GW consisting of two frequency components 9.0 and 9.7 GHz is obtained under the diode voltage and current 724 and 19.57 kA, corresponding to the conversion efficiency 41.5%. The conversion efficiency and the beating frequency are considerably stable with the diode voltage. The coaxial transmission supporter developed from our previous experimental research is employed to conductively connect the coaxial structure and to incoherently combine the microwave pulse of two frequencies with little reflection. It is found that the equipotential connection of the coaxial structure modifies the field distribution in the diode structure to facilitate the operation of the coaxial annular cathodes. The coaxial cathodes of different lengths are proved to be efficient at depressing the space charge effect in order to prevent the explosive emission of the inner cathode from being shielded by the outer annular beams.

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28

Mohsenpour, T., and B. Maraghechi. "Instability of wave modes in a free-electron laser with a helical wiggler and ion-channel guiding." Physics of Plasmas 15, no. 11 (November 2008): 113101. http://dx.doi.org/10.1063/1.3006089.

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29

DAMIANO, PETER A., R. D. SYDORA, and J. C. SAMSON. "Hybrid magnetohydrodynamic–kinetic model of standing shear Alfvén waves." Journal of Plasma Physics 69, no. 4 (July 29, 2003): 277–304. http://dx.doi.org/10.1017/s0022377803002216.

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We have developed a hybrid magnetohydrodynamics (MHD) –kinetic box model valid for standing shear Alfvén waves using the cold plasma MHD equations coupled to a system of kinetic electrons. The guiding centre equations are used for the motion of the electrons and the system is closed via an expression for the field-aligned electric field in terms of the perpendicular electric field and moments of the electron distribution function. The perpendicular electric fields are derived from the ideal MHD approximation. We outline the basic model equations and method of solution. Simulations are then presented comparing the hybrid model results with a cold plasma MHD model. Landau damping is shown to heavily damp the standing shear Alfvén wave in the hybrid simulations when $v_{th} \ge V_{A}$. The damping rate is shown to be in good agreement with the theoretical rate calculated for the model parameters.

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30

Bierwage, A., R. B. White, and A. Matsuyama. "Testing the conservative character of particle simulations: I. Canonical and noncanonical guiding center model in Boozer coordinates." Physics of Plasmas 29, no. 11 (November 2022): 113905. http://dx.doi.org/10.1063/5.0100303.

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The guiding center (GC) Lagrangian in Boozer coordinates for toroidally confined plasmas can be cast into canonical form by eliminating terms containing the covariant component [Formula: see text] of the magnetic field vector with respect to the poloidal flux function [Formula: see text]. In an unperturbed plasma, [Formula: see text] can be eliminated via exact coordinate transformations, but, in general, one relies on approximations, assuming that the effect of [Formula: see text] is small. Here, we are interested in the question whether Hamiltonian conservation laws are still satisfied when [Formula: see text] is retained in the presence of fluctuations. Considering fast ions in the presence of a shear Alfvén wave field with fixed amplitude, fixed frequency, and a single toroidal mode number n, we show that simulations using the code ORBIT with and without [Formula: see text] yield practically the same resonant and nonresonant GC orbits. The numerical results are consistent with theoretical analyses (presented in the appendix), which show that the unabridged GC Lagrangian with [Formula: see text] retained yields equations of motion that possess two key properties of Hamiltonian flows: (i) phase space conservation and (ii) energy conservation. As counter-examples, we also show cases where energy conservation (ii) or both conservation laws (i) and (ii) are broken by omitting certain small terms. When testing the conservative character of the simulation code, it is found to be beneficial to apply perturbations that do not resemble normal (eigen) modes of the plasma. The deviations are enhanced and, thus, more easily spotted when one inspects wave-particle interactions using nonnormal modes.

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31

Yalandin, M. I., G. A. Mesyats, V. V. Rostov, K. A. Sharypov, V. G. Shpak, S. A. Shunailov, and M. R. Ulmaskulov. "Compact Ka-Band Backward-Wave Generator of Superradiative Pulses Operating at Reduced Guiding Magnetic Field." IEEE Transactions on Plasma Science 36, no. 5 (October 2008): 2604–8. http://dx.doi.org/10.1109/tps.2008.2004244.

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32

Feng, Xiaojun, Qiming Zhang, and Muhammad Ali. "Explosion-Induced Stress Wave Propagation in Interacting Fault System: Numerical Modeling and Implications for Chaoyang Coal Mine." Shock and Vibration 2019 (November 11, 2019): 1–12. http://dx.doi.org/10.1155/2019/5856080.

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Exploring the propagation of stress waves in rocks with preexisting discontinuities is of great importance to reveal rock and geological engineering problems, particularly dynamic disasters like earthquakes and rockbursts in underground coal mining. In this paper, six 3D models established with COMSOL Multiphysics are employed to explore the influence of two preexisting faults with different orientations on the propagation process of explosion-induced stress waves and the reflection effect. Considering the propagation process of stress waves, the interactive effect between two different size faults is discussed. The results show that the dip angles of the preexisting fault and the differences of the elastic modulus, density, and Poisson’s ratio between faults and rocks have great influence on the distribution of stresses and strain-energy density. Immediately after the stress wave induced by blasting arrived at preexisting fault A, a relatively high concentration of the strain-energy density was observed at the last wave before passing through fault A. The presence of faults leads to the reflection of most of the blast energy. When the stress wave propagates across fault A, the strain energy stored in the stress wave becomes attenuated; thus, most strain energy was absorbed by the fault’s domain. Finally, the modeling results were implicated in Chaoyang Coal Mine to account for the distribution of the observed seismic events. This study has guiding significance for the attenuation law of stress waves passing through joint/fissure zones in geological engineering, earthquake engineering, and underground mining engineering.

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33

Rouhani, M. H., and B. Maraghechi. "Erratum: “Wave-mode dispersions in a relativistic electron beam with ion-channel guiding” [Phys. Plasmas 13, 083101 (2006)]." Physics of Plasmas 14, no. 2 (February 2007): 029902. http://dx.doi.org/10.1063/1.2458724.

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34

Su, Y., P. Chang, C. Lin, and A. S. Helmy. "Record Purcell factors in ultracompact hybrid plasmonic ring resonators." Science Advances 5, no. 8 (August 2019): eaav1790. http://dx.doi.org/10.1126/sciadv.aav1790.

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For integrated optical devices and traveling-wave resonators, realistic use of the superior wave-matter interaction offered by plasmonics is impeded by ohmic loss, which increases rapidly with mode volume reduction. In this work, we report composite hybrid plasmonic waveguides (CHPWs) that are not only capable of guiding subwavelength optical mode with long-range propagation but also unrestricted by stringent requirements in structural, material, or modal symmetry. In these asymmetric CHPWs, the versatility afforded by coupling dissimilar plasmonic modes provides improved fabrication tolerance and more degrees of device design optimization. Experimental realization of CHPWs demonstrates propagation loss and mode area of 0.03 dB/μm and 0.002 μm2, corresponding to the smallest combination among long-range plasmonic structures reported to date. CHPW ring resonators with 2.5-μm radius were realized with record Purcell factor compared with existing plasmonic and dielectric resonators of similar radii.

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35

Felsen, L. B. "Progressing and Oscillatory Waves for Hybrid Synthesis of Source-Excited Propagation and Diffraction." Journal of Applied Mechanics 52, no. 1 (March 1, 1985): 27–32. http://dx.doi.org/10.1115/1.3169022.

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Time-harmonic and transient propagation and diffraction phenomena can be described alternatively by progressing and oscillatory waves that express the wave motion in terms of direct and multiple wavefronts or rays, and in terms of resonances or modes, respectively. Each description is convenient and physically appealing when it requires few contributing elements. It is inconvenient and physically less transparent when it requires many elements, and it would then be desirable to combine many inconvenient elements into fewer convenient ones. For a variety of propagation environments, including layered or other guiding regions, this can be done by expressing a group of rays collectively in terms of modes, or a group of modes collectively in terms of rays. When this ray-mode equivalence is invoked selectively, there emerges a hybrid representation that combines ray fields and modal fields in uniquely defined proportions. The theory is based on Poisson summation and on alternative treatments of wave spectra. It has been applied to electromagnetics, underwater acoustics, and SH elastic motion, and is now being extended to general propagation in elastic media.

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36

Ling, Jun-Pu, Jun-Tao He, Jian-De Zhang, Tao Jiang, and Li-Li Song. "A Ku-band coaxial relativistic transit-time oscillator with low guiding magnetic field." Laser and Particle Beams 32, no. 2 (March 28, 2014): 295–303. http://dx.doi.org/10.1017/s0263034614000135.

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AbstractA novel coaxial relativistic transit-time oscillator with low guiding magnetic field is proposed and investigated to generate high power microwave at Ku-band. With the coaxial structure and a quasi body wave adopted as the operating mode, the device has a larger space-charge limiting current, higher power handling capacity, and lower guiding magnetic field. Moreover, for further improving the output power, a coaxial TM02mode resonant reflector is well designed. Main structure parameters of the device are optimized by particle in cell simulations. A typical simulation result is that, with a 358 keV, 7.25 kA beam guided by a magnetic field of about 0.7 T, an 810 MW microwave pulse at 14.25 GHz is generated, yielding a conversion efficiency of about 31%. The primary experiments are also carried out. At a low guiding magnetic field of 0.7 T, a microwave pulse with power of 400 MW, pulse duration of 30 ns, frequency of 14.3 GHz close to the simulation one, and efficiency of 15.4% is generated.

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37

Bierwage, A., and K. Shinohara. "Testing the conservative character of particle simulations: II. Spurious heating of guiding centers and full orbits subject to fluctuations expressed in terms of E and B." Physics of Plasmas 29, no. 11 (November 2022): 113906. http://dx.doi.org/10.1063/5.0106395.

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For an axisymmetric tokamak plasma, Hamiltonian theory predicts that the orbits of charged particles must stay on invariant tori of conserved energy in the moving frame of reference of a wave that propagates along the torus with fixed angular phase velocity, amplitude, and shape. The mode structure in the poloidal plane is arbitrary if the fluctuations are expressed in terms of potentials [Formula: see text] and [Formula: see text], which satisfy Faraday's law and the solenoidal condition by definition. Consequently, smoothing operations (such as gyroaveraging and noise suppression) do not violate the conservative laws. However, this is not guaranteed for models expressed in terms of the physical fields [Formula: see text] and [Formula: see text]. Here, we demonstrate that manipulations of [Formula: see text] and [Formula: see text] in the poloidal ( R, z) plane can cause spurious heating that is independent of time steps or numerical methods, but can be sensitive to geometry. In particular, we show that secular acceleration is enhanced when one imposes nonnormal modes that possess strong up–down asymmetry instead of the usual in–out asymmetry of normal toroidal (eigen)modes. We compare full gyro-orbit and guiding center models and find similar behavior. We also examine the effect of ad hoc N-point gyroaveraging in a guiding center model, as is done in some simulation codes. If one uses Faraday's law to (re)compute [Formula: see text] after gyroaveraging [Formula: see text], the guiding center motion remains conservative. Otherwise, spurious heating should be expected and monitored, but it may be tolerable when normal modes dominate.

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Pécseli, H. L., and T. Mikkelsen. "Turbulent diffusion in two-dimensional, strongly magnetized plasmas." Journal of Plasma Physics 34, no. 1 (August 1985): 77–94. http://dx.doi.org/10.1017/s0022377800002695.

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Particle diffusion is investigated in a strictly two-dimensional collisionless guiding-centre model for a strongly magnetized plasma. An analytical expression is presented for the entire time variation of the mean square test-particle displacement in the limit of low-frequency, strongly turbulent, electric field fluctuations. The analysis relies on an explicit integral expression for the Lagrangian autocorrelation function in terms of the Eulerian wavenumber spectrum and a time-varying weight function. Bohm diffusion is discussed by means of a simple model spectrum. The analysis applies for turbulent transport associated with electrostatic convective cells, magnetostatic cells and drift wave turbulence with the assumption of local homogeneity and isotropy in two dimensions.

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van Eester, D. "Semi-analytical modelling of non-local ion-cyclotron resonance heating in toroidal geometry." Journal of Plasma Physics 54, no. 1 (August 1995): 31–58. http://dx.doi.org/10.1017/s002237780001833x.

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A semi-analytical approach is proposed for computing the non-local response of a toroidal plasma to an electromagnetic perturbation. Although the perturbed distribution function as well as the absorbed power are also computed, the focus is on the associated quasi-linear diffusion operator. Different decorrelation models allow one to recapture the well-known ideal collisionless plasma result where the wave–particle energy exchange is exactly at resonance, as well as the more realistic plasma response where the interaction region is widened. The choice of the independent variables also allows one to carry out all computations except the integration of the guiding-centre motion analytically.

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Xiao, R. Z., X. W. Zhang, L. J. Zhang, X. Z. Li, L. G. Zhang, W. Song, Y. M. Hu, et al. "Efficient generation of multi-gigawatt power by a klystron-like relativistic backward wave oscillator." Laser and Particle Beams 28, no. 3 (September 2010): 505–11. http://dx.doi.org/10.1017/s0263034610000509.

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AbstractEfficient generation regime with a high power output has been experimentally realized in a klystron-like relativistic backward wave oscillator, in which a modulation cavity is inserted between the slow wave structure to decrease the energy spread of modulated beam electrons, and an extraction cavity is employed at the end of the slow wave structure to further recover energy from the electron beam. At a guiding magnetic field of 2.2 T, a microwave pulse with power of 6.5 GW, frequency of 4.26 GHz, pulse duration of 38 ns, and efficiency of 36% was generated when the diode voltage was 1.1 MV, and diode current was 16.4 kA. When the diode voltage was 820 kV, efficiency up to 47% with microwave power 4.4 GW was also realized experimentally.

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41

Singh, Arvinder, and Navpreet Singh. "Optical guiding of a laser beam in an axially nonuniform plasma channel." Laser and Particle Beams 28, no. 2 (April 12, 2010): 263–68. http://dx.doi.org/10.1017/s0263034610000133.

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AbstractThe guiding of a laser beam in a plasma channel formed by a short laser prepulse is investigated. Due to the self defocusing of an ionizing short laser prepulse, the plasma channel formed is axially nonuniform. When a delayed second laser beam is allowed to propagate through such a preformed plasma channel, convergence and divergence of the beam is observed due to the relative competition of the refraction and diffraction phenomenon. We have solved the wave equation governing the propagation characteristics of an ionizing prepulse and a delayed pulse by the moment theory approach. Results have been compared with the paraxial ray model of Liu and Tripathi (1994). The moment theory predicts the propagation of guided laser beam over several Rayleigh lengths.

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FAN, HONG-YI, and YONG REN. "A USEFUL REPRESENTATION FOR STUDYING QUANTUM HALL EFFECT." Modern Physics Letters B 10, no. 12 (May 20, 1996): 523–29. http://dx.doi.org/10.1142/s0217984996000572.

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We show that the complete and orthonormal representation 〈λ|, which is constructed in terms of guiding centers and canonical momenta for describing the coordinate of an electron in a uniform magnetic field, provides us with a direct algebraic approach to deriving the correct wave functions for studying quantum Hall effect. The squeezing transformation for electron’s motion radius in the 〈λ| representation is also discussed, normally ordered squeezing operators are derived by virtue of the technique of integration within an ordered product of operators.

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Oza, Anand U., Daniel M. Harris, Rodolfo R. Rosales, and John W. M. Bush. "Pilot-wave dynamics in a rotating frame: on the emergence of orbital quantization." Journal of Fluid Mechanics 744 (March 13, 2014): 404–29. http://dx.doi.org/10.1017/jfm.2014.50.

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AbstractWe present the results of a theoretical investigation of droplets walking on a rotating vibrating fluid bath. The droplet’s trajectory is described in terms of an integro-differential equation that incorporates the influence of its propulsive wave force. Predictions for the dependence of the orbital radius on the bath’s rotation rate compare favourably with experimental data and capture the progression from continuous to quantized orbits as the vibrational acceleration is increased. The orbital quantization is rationalized by assessing the stability of the orbital solutions, and may be understood as resulting directly from the dynamic constraint imposed on the drop by its monochromatic guiding wave. The stability analysis also predicts the existence of wobbling orbital states reported in recent experiments, and the absence of stable orbits in the limit of large vibrational forcing.

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Fan, Zhanfeng, and Jianhua Cai. "Effects of Unidirectional In Situ Stress on Crack Propagation of a Jointed Rock Mass Subjected to Stress Wave." Shock and Vibration 2021 (August 30, 2021): 1–13. http://dx.doi.org/10.1155/2021/5529540.

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This paper proposes a large-scale experiment combined with multiple cement mortar blocks to simulate stress wave propagation across a jointed rock mass under unidirectional in situ stress. Two identical mortar block models with smooth, dry, and unfilled joints were poured. The stress waves in Model 1 and Model 2 were generated by an electric spark source and a blast-induced source, respectively. The effects of these two excitation sources on stress wave propagation were compared through crack propagation experiments. The experimental results show that the peak value of the transmitted strain wave decreases as the in situ stress increases. The unidirectional in situ stress has a certain inhibitory effect on the stress wave propagation. It also indicates that for Model 1 with the electric spark source, no cracks on the upper surface, but a Livingstone blasting crater at the bottom is generated. For Model 2 with the blast-induced source, cracks on the upper surface and a blasting crater at the bottom are produced. The results verify the similarity between the electric spark source and the explosive source. The two-dimensional finite element program (ANSYS/LS-DYNA) was applied to further simulate the crack propagation of a jointed rock mass under different in situ stresses. The results of numerical simulation verify that the in situ stress has a clear guiding effect on the crack propagation.

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Kaps, Christian, and Rolf Göring. "On the generation of optically wave-guiding layers in silicate glasses by doping with heavy metals." Journal of Non-Crystalline Solids 90, no. 1-3 (February 1987): 573–76. http://dx.doi.org/10.1016/s0022-3093(87)80488-x.

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Ahmed, Fahad, Subrata Roy, Bikash Kumar Paul, Kawsar Ahmed, and Ali Newaz Bahar. "Extremely Low Loss of Photonic Crystal Fiber for Terahertz Wave Propagation in Optical Communication Applications." Journal of Optical Communications 41, no. 4 (April 28, 2020): 393–401. http://dx.doi.org/10.1515/joc-2018-0009.

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AbstractAn enormously low loss symmetrical hybrid decagonal porous core spiral photonic crystal fiber (SH-PCF) has been proposed for terahertz (THz) wave guiding. The modal characteristics of the fiber and its mathematical analysis have been numerically completed using a full-vector finite element method (FEM). Simulation results show an ultra-low material loss of 0.0167 cm−1 and large effective area 1.95×106 µm2 which is 91.6 % of bulk absorption material loss at controlling frequency f=1.0 THz with a core porosity 42 %. Additionally, proposed structure establishes the comparatively higher core power fraction maintaining lower scattering loss about 1.8×10−15 dB/cm at the same operating frequency. It promises the aforementioned advantages for efficient THz wave propagation.

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Cao, Jianqiu, Wenbo Liu, Hanyuan Ying, Jinbao Chen, and Qisheng Lu. "Numerical study on a single-mode continuous-wave thermally guiding very-large-mode-area fiber amplifier." Laser Physics 28, no. 3 (February 16, 2018): 035105. http://dx.doi.org/10.1088/1555-6611/aa9fb0.

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48

Tao, Shiquan, Shoufeng Gong, Joseph C. Fanguy, and Xuemei Hu. "The application of a light guiding flexible tubular waveguide in evanescent wave absorption optical sensing." Sensors and Actuators B: Chemical 120, no. 2 (January 2007): 724–31. http://dx.doi.org/10.1016/j.snb.2006.03.039.

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49

VARMA, RAM K. "Some surprising manifestations of charged particle dynamics in a magnetic field." Journal of Plasma Physics 76, no. 3-4 (January 15, 2010): 355–67. http://dx.doi.org/10.1017/s0022377809990626.

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AbstractWe present here some very unusual experimental results on the dynamics of charged particle in a magnetic field which cannot be comprehended in terms of the Lorentz dynamics regarded, as per the current conceptual framework, as the appropriate one for the macro-scale description. Astonishingly, these results have been shown to be manifestations of a novel macro-scale quantum structure, designated as ‘transition amplitude wave’ (TAW), riding with the guiding centre trajectory, which is generated in the latter trajectory in consequence of the scattering of the particle with a fixed scattering centre. One set of observed results is thus identified as matter wave interference effects on the macro-scale attributable to this entity. The other enigmatic observation demonstrates the detection of a curl-free magnetic vector potential on the macro-scale, which is also shown to be a consequence of the TAW embedded in the Lorentz trajectory. These enigmatic results thus point to the unravelling of a new concept of a ‘dressed’ Lorentz trajectory—dressed with the TAW—accountable for these results, as against the ‘bare’ trajectory. These results and the formalism which enables one to comprehend them have led to the emergence of a new class of phenomena which display quantum properties on the macro-scale.

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50

OTTAVIANI, MAURIZIO, and MARCO PETTINI. "TURBULENT DIFFUSION OF TEST PARTICLES IN STRONGLY MAGNETIZED PLASMAS." International Journal of Modern Physics B 05, no. 08 (May 10, 1991): 1243–62. http://dx.doi.org/10.1142/s0217979291000602.

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The motion of charged particles is described in the presence of a strong magnetic field and of an electric field made of three spatial Fourier modes whose amplitudes vary in time. The dynamics of the wave amplitudes is governed by a model of three interacting drift waves. For suitable parameter values of the three-wave model, chaotic solutions are found so that the Eulerian electric field is made of three turbulent modes. The E × B motion is described for charged particles in the guiding center approximation, which brings to nonlinear Hamiltonian equations of motion. The Hamiltonian (that coincides with the electric potential) is explicitly time-dependent through the temporal variation of the mode-amplitudes of the electric field, this fact is at the origin of the intrinsic chaoticity of particle dynamics (lagrangian chaos). Diffusive behaviour of particle trajectories is due to their intrinsic chaoticity and thus it is of non-collisional origin. Some results are reported concerning the particle dynamics when the Eulerian electric field is either quasi-periodically or chaotically varying in time. In particular, one finds different diffusion laws in the two cases (anomalous and classical respectively). The scaling behaviour of the diffusion coefficients (when the mean square displacement grows linearly in time) is reported. A simple stochastic model is also used to account for some of the observed features of particle diffusion.

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