L\'{e}vy flights in a steep potential well

TL;DR

This paper investigates Lévy flights in steep power-law potentials, revealing complex transient multimodal distributions, including tri-modal states, and provides phase diagrams and numerical methods for analyzing these phenomena.

Contribution

It extends previous work by analyzing Lévy flights in potentials with c>2, discovering transient tri-modality for c>4, and offering detailed proofs and numerical techniques.

Findings

Existence of transient tri-modal distributions for c>4

Bifurcation from mono- to bimodal distributions identified

Phase diagrams illustrating multimodal behaviors

Abstract

Lévy flights in steeper than harmonic potentials have been shown to exhibit finite variance and a critical time at which a bifurcation from an initial mono-modal to a terminal bimodal distribution occurs (Chechkin et al., Phys. Rev. E {\bf 67}, 010102(R) (2003)). In this paper, we present a detailed study of Lévy flights in potentials of the type U(x)∝|x|^c with c>2. Apart from the bifurcation into bimodality, we find the interesting result that for c>4 a trimodal transient exists due to the temporal overlap between the decay of the central peak around the initial $\delta$-condition and the building up of the two emerging side-peaks, which are characteristic for the stationary state. Thus, for certain system parameters there exists a transient tri-modal distribution of the Lévy flight. These properties of LFs in external potentials of the power-law type can be represented by certain phase diagrams. We also present details about the proof of multi-modality and the numerical procedures to establish the probability distribution of the process.