Rest Frame Interference in Rotating Structures and Metamaterials.

Using the formulation of electrodynamics in rotating media, we put into explicit quantitative form the effect of rotation on interference and diffraction patterns as observed in the rotating medium's rest frame. As a paradigm experiment we focus the interference generated by a linear array of sources in a homogeneous medium. The interference is distorted due to rotation; the maxima now follow curved trajectories.

Finite-difference time-domain study of modulated and disordered coupled resonator optical waveguide rotation sensors.

We present a full-wave finite difference time domain (FDTD) study of a coupled resonator optical waveguide (CROW) rotation sensor consisting of 8 doubly degenerate ring resonators. First we demonstrate the formation of rotation-induced gap in the spectral pass-band of the CROW and show the existence of a dead-zone at low rotation rates which is mainly due to its finite size and partly because of the individual cavities losses. In order to overcome this deficiency, we modulate periodically the refractive indices of the resonators to effectively move CROW's operating point away from this dead-zone.

Metaweaves: sector-way nonreciprocal metasurfaces.

Confluent with the single dimension of time, breach of time-reversal symmetry is usually perceived as a one-dimensional concept. In its ultimate realization-the one-way guiding device-it allows optical propagation in one direction, say +z, and forbids it in the opposite direction -z. Hence, in studies of time-reversal asymmetry the mapping t↦-t is naturally associated with z↦-z.

Unconditionally stable finite-difference time-domain methods for modeling the Sagnac effect.

We present two unconditionally stable finite-difference time-domain (FDTD) methods for modeling the Sagnac effect in rotating optical microsensors. The methods are based on the implicit Crank-Nicolson scheme, adapted to hold in the rotating system reference frame-the rotating Crank-Nicolson (RCN) methods. The first method (RCN-2) is second order accurate in space whereas the second method (RCN-4) is fourth order accurate.

One way optical waveguides for matched non-reciprocal nanoantennas with dynamic beam scanning functionality.

Matching circuits for waveguide-nanoantenna connections are difficult to implement. However, if the waveguide permits only one-way propagation, the matching issue disappears since back-reflections cannot take place; the feed signal is converted to radiation at high efficiency. Hence, a terminated one-way waveguide may serve as an assembly consisting of a waveguide, a matching mechanism, and an antenna.

Parametric plasmonics and second harmonic generation in particle chains.

Parametric optics and second harmonic generation in pure plasmonic particle chains are studied. By a proper design of the plasmonic particle geometry, the modes supported by the chain can achieve phase-matching conditions. Then the magnetic-field dependence of the plasmon electric susceptibility can provide the nonlinearity and the coupling mechanism leading to parametric processes, sum frequency and second harmonic generation.

Magnetized spiral chains of plasmonic ellipsoids for one-way optical waveguides.

When a linear chain of plasmonic nanoparticles is subject to longitudinal magnetic field, it exhibits optical Faraday rotation. If the magnetized nanoparticles are plasmonic ellipsoids arranged as a spiral chain, the interplay between the Faraday rotation and the geometrical spiral rotation (structural chirality) can strongly enhance nonreciprocity. This interplay forms a waveguide that permits one-way propagation only, within four disjoint frequency bands, two bands for each direction.

Two-dimensional Green's function theory for the electrodynamics of a rotating medium.

We derive an exact spectral representation for the Green's function of Maxwell equations in a two-dimensional homogeneous and rotating environment. The formulation is developed in the medium (noninertial) rest frame, and it represents the response to a point source, where both the source and observation points rotate together with the medium. The closed form expression for the Green's function is derived for (nonrelativistic) slowly rotating media at finite distances.

Rotating photonic crystals: a medium for compact optical gyroscopes.

The effect of rotation of a photonic crystal that contains a set of microcavities is studied using the formulation of electrodynamics in rotating media. A new manifestation of the Sagnac effect is observed. It is shown that the phase shift or frequency difference between rotation-codirected and rotation-counterdirected propagations depends on a set of parameters not previously reported.

Sensitivity analysis of narrowband photonic crystal filters and waveguides to structure variations and inaccuracy.

Photonic crystal microcavities, formed by local defects within an otherwise perfectly periodic structure, can be used as narrowband optical resonators and filters. The coupled-cavity waveguide (CCW) is a linear array of equally spaced identical microcavities. Tunneling of light between microcavities forms a guiding effect, with a central frequency and bandwidth controlled by the local defects' parameters and spacing, respectively.