Amplitude and Gradient Scattering in Waveguides with Corrugated Surfaces

TL;DR

This paper investigates how gradient scattering affects eigenstates in periodic waveguides with corrugated surfaces, revealing that even small amplitude variations can cause significant scattering due to large gradients.

Contribution

It introduces the concept of gradient scattering in waveguides and demonstrates its strong impact even with minimal amplitude variations, combining numerical and theoretical analysis.

Findings

Gradient scattering can be strong despite small amplitude of surface corrugation.

Large gradients in the walls significantly influence eigenstate properties.

Numerical and theoretical methods confirm the importance of gradient effects.

Abstract

We study chaotic properties of eigenstates for periodic quasi-1D waveguides with "regular" and "random" surfaces. Main attention is paid to the role of the so-called "gradient scattering" which is due to large gradients in the scattering walls. We demonstrate numerically and explain theoretically that the gradient scattering can be quite strong even if the amplitude of scattering profiles is very small in comparison with the width of waveguides.