# Electromagnetic Scattering Laws in Weyl Systems

## TL;DR

This paper introduces new electromagnetic scattering laws in Weyl systems that enable control over scattering cross sections independently of wavelength, unlike traditional laws based on free space dispersion.

## Contribution

It presents novel scattering laws in Weyl systems that decouple cross section behavior from wavelength limits, expanding control over wave-matter interactions.

## Key findings

- Weyl systems allow divergence of cross sections at non-zero frequencies.
- Decoupling of cross section from wavelength in Weyl systems.
- Potential for tailored electromagnetic interactions across frequencies.

## Abstract

Wavelength determines the length scale of the cross section when electromagnetic waves are scattered by an electrically small object. The cross section diverges for resonant scattering, and diminishes for non-resonant scattering, when wavelength approaches infinity. This scattering law explains the color of the sky as well as the strength of a mobile phone signal. We show that such wavelength scaling comes from free space's conical dispersion at zero frequency. Emerging Weyl systems, offering similar dispersion at non-zero frequencies, lead to new laws of electromagnetic scattering that allow cross sections to be decoupled from the wavelength limit. Diverging and diminishing cross sections can be realized at any target wavelength in a Weyl system, providing unprecedented ability to tailor the strength of wave-matter interactions for radio-frequency and optical applications.

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Source: https://tomesphere.com/paper/1705.05059