# Fresnel drag in space-time modulated metamaterials

## TL;DR

This paper demonstrates that space-time modulated metamaterials can mimic Fresnel drag effects typically caused by physical motion, using phased permittivity and permeability modulations to emulate relativistic phenomena without actual movement.

## Contribution

It introduces a novel approach to replicate relativistic Fresnel drag effects through space-time metamaterials with modulated electromagnetic parameters.

## Key findings

- Space-time modulation can mimic Fresnel drag effects.
- Effective bianisotropic parameters represent the metamaterials.
- Transmission line model supports the theoretical findings.

## Abstract

A moving medium drags light along with it as measured by Fizeau and explained by Einstein's theory of special relativity. Here we show that the same effect can be obtained in a situation where there is no physical motion of the medium. Modulations of both the permittivity and permeability, phased in space and time in the form of travelling waves, are the basis of our model. Space-time metamaterials are represented by effective bianisotropic parameters, which can in turn be mapped to a moving homogeneous medium. Hence these metamaterials mimic a relativistic effect without the need for any actual material motion. We discuss how both the permittivity and permeability need to be modulated in order to achieve these effects, and we present an equivalent transmission line model.