PROPAGATING MODES OF A HETEROGENEOUS, MACRO-HOMOGENEOUS CONTINUUM

Correlations of heterogeneous wave fields propagating in homogeneous media

The paper concerns the analysis of the correlations of wave fields propagating in heterogeneous media. We show that selected field-field correlations asymptotically propagate in non-scattering media, i.e., propagate as if the underlying medium was homogeneous. Such correlations are therefore good candidates for imaging strategies in heterogeneous media based on back-propagations in a homogeneou...

Observation of propagating edge spin waves modes

Homogeneous Modes of Cosmological Instantons

We discuss the O(4) invariant perturbation modes of cosmological instantons. These modes are spatially homogeneous in Lorentzian spacetime and thus not relevant to density perturbations. But their properties are important in establishing the meaning of the Euclidean path integral. If negative modes are present, the Euclidean path integral is not well defined, but may nevertheless be useful in a...

Propagating modes in subwavelength cylindrical holes

We analyze subwavelength cylindrical holes in an optically thick metallic film with the metal described by a plasmonic model. We emphasize that such holes always support propagating modes near the surface plasmon frequency, regardless of how small the holes are. Based on this analysis, we design both single holes and hole arrays in which propagating modes play a dominant role in the transport p...

Nonlinear localized and propagating modes in metamaterials

Discrete magnetic metamaterials (MMs) comprised, e.g. of periodically arranged nonlinear split-ring resonators (SRRs), may support highly localized excitations in the form of discrete breathers (DBs) [1]. In practice, the SRRs can become nonlinear by the insertion of nonlinear electronic components into their slits [2]. Recently, a novel MM comprised of two types of SRRs was investigated theore...