Wave transmission and its universal fluctuations in one-dimensional systems with L\'evy-like disorder: Schr\"odinger, Klein-Gordon and Dirac equations

TL;DR

This paper studies wave transmission in one-dimensional systems with Le9vy-like disorder, revealing universal fluctuation behavior and transitions between anomalous and standard localization across different wave equations.

Contribution

It provides a comprehensive analysis of wave localization and transmission fluctuations in Le9vy-disordered systems, including relativistic and non-relativistic waves, with new insights into universal fluctuation properties.

Findings

Transmission follows  power-law decay with length for certain disorder cases.

A transition between anomalous and standard localization occurs with increasing energy.

Transmission fluctuations are universal, independent of system specifics.

Abstract

We investigate the propagation of waves in one-dimensional systems with L\'evy-type disorder. We perform a complete analysis of non-relativistic and relativistic wave transmission submitted to potential barriers whose width, separation or both follow L\'evy distributions characterized by an exponent $0 < \alpha <1$. For the first two cases, where one of the parameters is fixed, non-relativistic and relativistic waves present anomalous localization, $\langle T \rangle \propto L^{-\alpha}$. However, for the latter case, in which both parameters follow a L\'evy distribution, non-relativistic and relativistic waves present a transition between anomalous and standard localization as the incidence energy increases relative to the barrier height. Moreover, we obtain the localization diagram delimiting anomalous and standard localization regimes, in terms of incidence angle and energy. Finally, we verify that transmission fluctuations, characterized by its standard deviation, are universal, independent of barrier architecture, wave equation type, incidence energy and angle, further extending earlier studies on electronic localization.