Pure nonlinear optical activity in metamaterials

We demonstrate a type of meta-atom for creating metamaterials with giant nonlinear optical activity but vanishing linear optical activity in a wide frequency range. Such properties are not found in any natural materials, and we call this regime as pure nonlinear optical activity. We further extend our design concept and show that the metamaterial can be tuned dynamically to exhibit either positive or negative polarization rotation.The work was supported by the Australian Research Council through Discovery Projects scheme

Nonlinear guided waves and symmetry breaking in left-handed waveguides

We analyze nonlinear guided waves in a planar waveguide made of a left-handed material surrounded by a Kerr-like nonlinear dielectric. We predict that such a waveguide can support fast and slow symmetric and antisymmetric nonlinear modes. We study the symmetry breaking bifurcation and asymmetric modes in such a symmetric structure. We analyze nonlinear dispersion properties of the guided waves, and show that the modes can be both forward and backward.Comment: 4 pages, 3 figure

Multistability in nonlinear left-handed transmission lines

Employing a nonlinear left-handed transmission line as a model system, we demonstrate experimentally the multi-stability phenomena predicted theoretically for microstructured left-handed metamaterials with a nonlinear response. We show that the bistability is associated with the period doubling which at higher power may result in chaotic dynamics of the transmission line

Effect of microscopic disorder on magnetic properties of metamaterials

We analyze the effect of microscopic disorder on the macroscopic properties of composite metamaterials and study how weak statistically independent fluctuations of the parameters of the structure elements can modify their collective magnetic response and left-handed properties. We demonstrate that even a weak microscopic disorder may lead to a substantial modification of the metamaterial magnetic properties, and a 10% deviation in the parameters of the microscopic resonant elements may lead to a substantial suppression of the wave propagation in a wide frequency range. A noticeable suppression occurs also if more than 10% of the resonant magnetic elements possess strongly different properties, and in the latter case the defects can create an additional weak resonant line. These results are of a key importance for characterizing and optimizing novel composite metamaterials with the left-handed properties at terahertz and optical frequencies

Excitation of guided waves in layered structures with negative refraction

We study the electromagnetic beam reflection from layered structures that include the so-called double-negative materials, also called left-handed metamaterials. We predict that such structures can demonstrate a giant lateral Goos-Hanchen shift of the scattered beam accompanied by splitting of the reflected and transmitted beams due to the resonant excitation of surface waves at the interfaces between the conventional and double-negative materials as well as due to excitation of leaky modes in the layered structures. The beam shift can be either positive or negative, depending on the type of the guided waves excited by the incoming beam. We also perform finite-difference time-domain simulations and confirm the major effects predicted analytically.Comment: 13 pqages, 10 figures. Also available at http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-2-48

Giant Goos-Hanchen effect at the reflection from left-handed metamaterials

We study the beam reflection from a layered structure with a left-handed metamaterial. We predict a giant lateral (Goos-Hanchen) shift and splitting of the beam due to the resonant excitation of surface polaritons with a vortex-like energy flow between the right- and left-handed materials

Parametric metasurfaces for electromagnetic wave amplification

We study parametric amplification of electromagnetic waves by metasurfaces. We design a variable capacitor-loaded metasurface that is able to amplify incident electromagnetic waves. We analyze various regimes of operation of the system and find that we can achieve a significant gain (over 10 dB) in just one layer of such structure, and this gain can be controlled by the parametric modulation. We study the instability threshold for this system and show that a simple theoretical model agrees well with the results of full numerical simulations.Comment: The following article has been submitted to Applied Physics Letters. After it is published, it will be found at https://pubs.aip.org/aip/ap