We theoretically investigate the existence and properties of hybrid surface waves forming at interfaces between left-handed materials and dielectric birefringent media. The existence conditions of such waves are found to be highly relaxed in comparison to the original hybrid surface waves, discovered by Dyakonov, in configurations involving birefringent materials and right-handed media. Hybrid surface waves in left-handed materials feature remarkable properties: (i) a high degree of localization and (ii) coexistence of several guided solutions. The existence of several hybrid surface waves for the same parameter set is linked to the birefringent nature of the medium whereas the strong localization is related to the presence of the left-handed material. The hybrid surface modes appear for large areas in the parameter space.
The propagation of electromagnetic surface waves guided by the planar interface of two isotropic chiral materials, namely materials $calA$ and $calB$, was investigated by numerically solving the associated canonical boundary-value problem. Isotropic chiral material $calB$ was modeled as a homogenized composite material, arising from the homogenization of an isotropic chiral component material and an isotropic achiral, nonmagnetic, component material characterized by the relative permittivity $eps_a^calB$. Changes in the nature of the surface waves were explored as the volume fraction $f_a^calB$ of the achiral component material varied. Surface waves are supported only for certain ranges of $f_a^calB$; within these ranges only one surface wave, characterized by its relative wavenumber $q$, is supported at each value of $f_a^calB$. For $mbox{Re} lec eps_a^calB ric > 0 $, as $left| mbox{Im} lec eps_a^calB ric right|$ increases surface waves are supported for larger ranges of $f_a^calB$ and $left| mbox{Im} lec q ric right|$ for these surface waves increases. For $mbox{Re} lec eps_a^calB ric < 0 $, as $ mbox{Im} lec eps_a^calB ric $ increases the ranges of $f_a^calB$ that support surface-wave propagation are almost unchanged but $ mbox{Im} lec q ric $ for these surface waves decreases. The surface waves supported when $mbox{Re} lec eps_a^calB ric < 0 $ may be regarded as akin to surface-plasmon-polariton waves, but those supported for when $mbox{Re} lec eps_a^calB ric > 0 $ may not.
We investigate repulsive Casimir force between slabs containing left-handed materials with controllable electromagnetic properties. The sign of Casimir force is determined by the electric and magnetic properties of the materials, and it is shown that the formation of the repulsive force is related to the wave impedances of two slabs. The sign change of the Casimir force as a function of the distance is studied. Special emphasis is put on the restoring Casimir force which may be found to exist between perfectly conducting material and metamaterial slabs. This restoring force is a natural power for the system oscillation in vacuum and also can be used for system stabilization.
Using detailed simulations we investigate the magnetic response of metamaterials consisting of pairs of parallel slabs or combinations of slabs with wires (including the fishnet design) as the length-scale of the structures is reduced from mm to nm. We observe the expected saturation of the magnetic resonance frequency when the structure length-scale goes to the sub-micron regime, as well as weakening of the effective permeability resonance and reduction of the spectral width of the negative permeability region. All these results are explained by using an equivalent resistor-inductor-capacitor (RLC) circuit model, taking into account the current-connected kinetic energy of the electrons inside the metallic parts through an equivalent inductance, added to the magnetic field inductance in the unit-cell. Using this model we derive simple optimization rules for achieving optical negative permeability metamaterials of improved performance. Finally, we analyze the magnetic response of the fishnet design and we explain its superior performance regarding the high attainable magnetic resonance frequency, as well as its inferior performance regarding the width of the negative permeability region.
By studying the rotations of the polarization of light propagating in right and left handed films, with emphasis on the transmission (Faraday effect) and reflec- tions (Kerr effect) of light and through the use of complex values representing the rotations, it can be shown that the real portions of the complex angle of Faraday and Kerr rotations are odd functions with respect to the refractive index n and that the respective imaginary portions of the angles are an even function of n. Multiple reflections within the medium lead to the maximums of the real portions of Faraday and Kerr effects to not coincide with zero ellipticity. It will also be shown that in the thin film case with left handed materials there are large resonant enhancements of the reflected Kerr angle that could be obtained experimentally.
In the present work, we explore soliton and rogue-like wave solutions in the transmission line analogue of a nonlinear left-handed metamaterial. The nonlinearity is expressed through a voltagedependent and symmetric capacitance motivated by the recently developed ferroelectric barium strontium titanate (BST) thin film capacitor designs. We develop both the corresponding nonlinear dynamical lattice, as well as its reduction via a multiple scales expansion to a nonlinear Schrodinger (NLS) model for the envelope of a given carrier wave. The reduced model can feature either a focusing or a defocusing nonlinearity depending on the frequency (wavenumber) of the carrier. We then consider the robustness of different types of solitary waves of the reduced model within the original nonlinear left-handed medium. We find that both bright and dark solitons persist in a suitable parametric regime, where the reduction to the NLS is valid. Additionally, for suitable initial conditions, we observe a rogue wave type of behavior, that differs significantly from the classic Peregrine rogue wave evolution, including most notably the breakup of a single Peregrine-like pattern into solutions with multiple wave peaks. Finally, we touch upon the behavior of generalized members of the family of the Peregrine solitons, namely Akhmediev breathers and Kuznetsov-Ma solitons, and explore how these evolve in the left-handed transmission line.
Lucian-Cornel Crasovan
,Osamu Takayama
,David Artigas
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(2006)
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"Surface waves at the interface between left-handed and birefringent materials"
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Steffen Johansen Dr.
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