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arXiv · 2509.26501

Quantum fermion emission from excited kinks

Sergio Alameda-Calvo·Jose J. Blanco-Pillado·Alberto García Martín-Caro
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Abstract

The amplitude of an excited shape mode in a kink is expected to decay with a well-known power law via scalar radiation emission due to the nonlinear self-coupling of the scalar field. In this work we propose an alternative decay mechanism via pair production of fermions in a simple extension of the $\phi^4$ model in which the scalar field is coupled to a (quantum) fermionic field through a Yukawa-like interaction term. We study the power emitted through fermions as a function of the coupling constant in the semi-classical limit (without backreaction) and compare it to the case of purely scalar radiation emission.

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Sergio Alameda-Calvo, Jose J. Blanco-Pillado, Alberto García Martín-Caro. 2025-09-30. Quantum fermion emission from excited kinks. https://arxiv.org/abs/2509.26501

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