Two-point paraxial traveltimes in an inhomogeneous anisotropic medium

Stokes-vector evolution in a weakly anisotropic inhomogeneous medium.

The equation for evolution of the four-component Stokes vector in weakly anisotropic and smoothly inhomogeneous media is derived on the basis of a quasi-isotropic approximation of the geometrical optics method, which provides the consequent asymptotic solution of Maxwell's equations. Our equation generalizes previous results obtained for the normal propagation of electromagnetic waves in strati...

A level set based Eulerian method for paraxial multivalued traveltimes

We apply the level-set methodology to compute multivalued solutions of the paraxial eikonal equation in both isotropic and anisotropic metrics. This paraxial equation is obtained from 2D stationary eikonal equations by using one of the spatial directions as the artificial evolution direction. The advection velocity field used to move level sets is obtained by the method of characteristics; ther...

3D Eikonal Solvers, Part II: Anisotropic Traveltimes

In anisotropic media the direction of energy propagation is not in general tangent to the wavefront normal. On the other hand, nite di erence eikonal solvers compute the solution based on the traveltime gradient and the wavefront normal. Local convexity of the wavefronts in transverse isotropic (TI) media is studied for the eikonal solver to determine the correct upwind direction of the energy ...

Casimir stress in an inhomogeneous medium

The Casimir effect in an inhomogeneous dielectric is investigated using Lifshitz’s theory of electromagnetic vacuum energy. A permittivity function that depends continuously on one Cartesian coordinate is chosen, bounded on each side by homogeneous dielectrics. The result for the Casimir stress is infinite everywhere inside the inhomogeneous region, a divergence that does not occur for piece-wi...

Wave Propagation in an Inhomogeneous Medium