Wave Deflection and Shifted Refocusing in a Medium Modulated by a Superluminal Rectangular Pulse

TL;DR

This paper investigates how superluminal rectangular pulse modulations in a medium cause wave deflection and shifted refocusing, revealing unique scattering behaviors such as retro-directive deflection and spatially shifted refocusing.

Contribution

It introduces a novel analysis of wave scattering in superluminal modulated media using a moving frame approach and graphical methods.

Findings

Superluminal modulations cause retro-directive wave deflection.

Cylindrical waves are refocused at shifted spatial points.

The approach simplifies analysis by transforming to a purely temporal modulation frame.

Abstract

We explore the problem of scattering in a medium modulated by a superluminal rectangular pulse, with the pulse modulation realized through transverse excitations. We solve this problem in the moving frame where the modulation appears purely temporal, since the solution to a purely temporal modulation is known. Upon this basis, we use a graphical approach to find the angle and frequency of the wave scattered by the modulation under oblique incidence. This study reveals that superluminal modulations deflect plane waves retro-directively, and refocus cylindrical waves to a shifted point of space with respect to the original source.