Transmission properties of left-handed band-gap structures

We analyze transmission of electromagnetic waves through a periodic band-gap structure consisting of slabs of a left-handed metamaterial and air. Using the effective parameters of the metamaterial derived from its microscopic structure, we study, with the help of the transfer-matrix approach and by means of the finite-difference-time-domain numerical simulations, the transmission properties of such a left-handed photonic crystals in a novel type of band gap associated with the zero averaged refractive index. We demonstrate that the transmission can be made tunable by introducing defects, which allow to access selectively two different types of band gaps.Comment: 5 pages, 8 figure

Subwavelength imaging with opaque left-handed nonlinear lens

We introduce the concept of subwavelength imaging with an opaque nonlinear left-handed lens by generating the second-harmonic field. We consider a slab of composite left-handed metamaterial with quadratic nonlinear response and show that such a flat lens can form, under certain conditions, an image of the second-harmonic field of the source being opaque at the fundamental frequency.Comment: 3 pages, 3 figure

Birefringent left-handed metamaterials and perfect lenses

We describe the properties of birefringent left-handed metamaterials and introduce the concept of a birefringent perfect lens. We demonstrate that, in a sharp contrast to the conventional left-handed perfect lens at $\epsilon=\mu=-1$, where $\epsilon$ is the dielectric constant and $\mu$ is the magnetic permeability, the birefringent left-handed lens can focus either TE or TM polarized waves or both of them, allowing a spatial separation of the TE and TM images. We discuss several applications of the birefringent left-handed lenses such as the beam splitting and near-field diagnostics at the sub-wavelength scale.Comment: 4 pages 6 figure

Nonlinear magnetoinductive waves and domain walls in composite metamaterials

We describe novel physics of nonlinear magnetoinductive waves in left-handed composite metamaterials. We derive the coupled equations for describing the propagation of magnetoinductive waves, and show that in the nonlinear regime the magnetic response of a metamaterial may become bistable. We analyze modulational instability of different nonlinear states, and also demonstrate that nonlinear metamaterials may support the propagation of domain walls (kinks) connecting the regions with the positive and negative magnetization.Comment: 5 pages, 5 figure

Nonlinear left-handed metamaterials

We analyze nonlinear properties of microstructured materials with negative refraction, the so-called left-handed metamaterials. We demonstrate that the hysteresis-type dependence of the magnetic permeability on the field intensity allows changing the material properties from left- to right-handed and back. Using the finite-difference time-domain simulations, we study wave transmission through the slab of nonlinear left-handed material, and predict existence of temporal solitons in such materials. We demonstrate also that nonlinear left-handed metamaterials can support both TE- and TM-polarized self-trapped localized beams, spatial electromagnetic solitons. Such solitons appear as single- and multi-hump beams, being either symmetric or antisymmetric, and they can exist due to the hysteresis-type magnetic nonlinearity and the effective domains of negative magnetic permeability.Comment: 7 pages, 8 figure

Ideal and nonideal electromagnetic cloaks

We employ the analytical results for the spatial transformation of the electromagnetic fields to obtain and analyze explicit expressions for the structure of the electromagnetic fields in invisibility cloaks, beam splitters, and field concentrators. We study the efficiency of nonideal electromagnetic cloaks and discuss the effect of scattering losses on the cloak invisibility.Comment: 4 pages, 2 figure

Highly Efficient Broadband Light Absorber Based on Nonuniform Hyperbolic Metamaterial Film

We develop a concept of highly efficient broadband light absorber based on nonuniform hyperbolic metamaterial. We suggest a gradual bending of the anisotropy axis inside the metamaterial that results in spatial shift of the area of resonant absorption depending on the incidence angle. In this resonant region the wavevector of light is parallel to the generatrix of resonant cone and the radiation losses are maximal because of extremely high value of refraction index. Changing the radiation frequency also shifts the spatial position of the resonant region so that high level of absorption may be achieved in wide frequency range. Using the model of nanowire medium (silver wires in silica host) we predict that 200 nm film of this hyperbolic metamaterial allows reaching almost total absorption of radiation throughout the visible band

Grading plasmonic nanoparticles with light

We introduce an approach for fine grading of plasmonic ellipsoidal nanoparticles by two interfering light beams. We consider electrically neutral subwavelength metal nanoparticles whose response is described within the dipole approximation. For the ellipsoidal nanoparticles, we find that their polarizability tensor is strongly dispersive due to the existence of two orthogonal plasmon modes. These modes can be resonantly excited by light and the optical force experienced by particles depends on the ratio of ellipsoid semiaxes. This dependence allows us to spatially separate ellipsoidal particles with different aspect ratio. The eigenfrequencies of plasmons depend on the depolarization factor as well as on the permittivity of the environment and therefore our results can potentially be employed in a wide frequency range including near infrared, visible, and ultraviolet

Nonlinear control of invisibility cloaking

We introduce a new concept of the nonlinear control of invisibility cloaking. We study the scattering properties of multi-shell plasmonic nanoparticles with a nonlinear response of one of the shells, and demonstrate that the scattering cross-section of such particles can be controlled by a power of the incident electromagnetic radiation. More specifically, we can either increase or decrease the scattering cross-section by changing the intensity of the external field, as well as control the scattering efficiently and even reverse the radiation direction.This work was supported by the Australian Research Council and the Ministry of Education and Science of Russian Federation, NAZ and AAZ acknowledge a support from the Russian Fund for Basic Research (grants 11-02-00531, 11-02-97058)

Light scattering by nonlinear cylindrical multilayer structures

We study light scattering by cylindrical multilayer structures containing Kerr-type nonlinear materials. We develop a new semi-analytical method for solving such nonlinear problems by reducing the original 2D system by a 1D nonlinear Helmholtz equation. We apply our method for the case of wave scattering by the core-shell metal-dielectric nanowire and show that the nonlinearity allows us to control scattering cross section, which in the resonant regime demonstrates optical bistability. We compare our method with the finite-difference time-domain (FDTD) approach and find that the new approach is accurate and is 105 times faster and more numerically robust than the FDTD.A. E. M. and I. V. S. would like to acknowledge support from the Australian Research Council through the Future Fellowship (FT110100037) and Discovery Projects. NAZ acknowledges support from the Russian Fund for Basic Research through grant no. 13-02-97115