Resonance spectrum of a bulk fermion on branes

TL;DR

This paper compares two mechanisms for localizing bulk fermions on branes, analyzing their resonance spectra and finding that both produce volcano-like potentials with localized zero modes and multiple resonances.

Contribution

It investigates and compares the localization and resonance spectra of bulk fermions on branes using two different coupling mechanisms, revealing their effects on fermion resonances.

Findings

Both mechanisms produce volcano-like potentials.

Left-chiral zero modes are localized on the brane.

Number of fermion resonances increases linearly with coupling parameter.

Abstract

It is known that there are two mechanisms for localizing a bulk fermion on a brane, one is the well-known Yukawa coupling and the other is the new coupling proposed in [Phys. Rev. D 89, 086001 (2014)]. In this paper, we investigate localization and resonance spectrum of a bulk fermion on the same branes with the two localization mechanisms. It is found that both the two mechanisms can result in a volcano-like effective potential of the fermion Kaluza-Klein modes. The left-chiral fermion zero mode can be localized on the brane and there exist some discrete massive fermion Kaluza-Klein modes that quasilocalized on the brane (also called fermion resonances). The number of the fermion resonances increases linearly with the coupling parameter.