Refractive index modulation in media with saturable photosensitivity

Refraction in media with a negative refractive index.

We show that an electromagnetic (EM) wave undergoes negative refraction at the interface between a positive and negative refractive index material, the latter being a properly chosen photonic crystal. Finite-difference time-domain (FDTD) simulations are used to study the time evolution of an EM wave as it hits the interface. The wave is trapped temporarily at the interface, reorganizes, and, af...

Refractive-index measurement of absorbing condensed media.

Broadband, Volumetric Negative-Refractive-Index Media

Broadband, Volumetric Negative-Refractive-Index Media by Scott M. Rudolph Chair: Anthony Grbic Since their invention, negative-refractive-index (NRI) media have been plagued by three primary limitations: narrow bandwidth, high loss and polarization dependence. In this thesis, each of these problems is addressed. First, a new metamaterial topology that achieves negative permeability over a broad...

Resolving the wave vector in negative refractive index media.

We address the general issue of resolving the wave vector in complex electromagnetic media including negative refractive media. This requires us to make a physical choice of the sign of a square root imposed merely by conditions of causality. By considering the analytic behavior of the wave vector in the complex plane, it is shown that there are a total of eight physically distinct cases in the...

Measurements of nonlinear refractive index in scattering media.

We have recently developed a spectral re-shaping technique to simultaneously measure nonlinear refractive index and nonlinear absorption. In this technique, the information about the nonlinearities is encoded in the frequency domain, rather than in the spatial domain as in the conventional Z-scan method. Here we show that frequency encoding is much more robust with respect to scattering. We com...