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arXiv · 1004.2181

Effects of the variation of mass on fermion localization and resonances on thick branes

Zhen-Hua Zhao·Yu-Xiao Liu·Hai-Tao Li·Yong-Qiang Wang
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Abstract

A few years ago, Campos investigated the critical phenomena of thick branes in warped spacetimes [Phys. Rev. Lett. {\bf 88} (2002) 141602]. Inspired by his work, we consider a toy model of thick branes generated by a real scalar field with the potential $V(ϕ)=aϕ^2-bϕ^4+cϕ^6$, and investigate the variation of the mass parameter $a$ on the branes as well as the localization and resonances of fermions. An interesting result is found: there is a critical value for the mass parameter $a$, and when the critical value of $a$ is reached the solution of the background scalar field is not unique and has the shape of a double kink. This happens in both cases with and without gravity. It is also shown that the numbers of the bound Kaluza-Klein modes of fermions on the gravity-free brane and the resonant states of fermions on the brane with gravity increase with the value of $a$.

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Zhen-Hua Zhao, Yu-Xiao Liu, Hai-Tao Li, Yong-Qiang Wang. 2010-10-26. Effects of the variation of mass on fermion localization and resonances on thick branes. https://doi.org/10.1103/physrevd.82.084030

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