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arXiv · 2604.13674

Axion Inflation from Heavy-Fermion One-Loop Effects

Kai-Ge Zhang·Jian-Feng He·Chengjie Fu·Zong-Kuan Guo
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Abstract

We derive a one-loop effective description of axion inflation by integrating out a heavy Dirac fermion with an inflaton-dependent complex mass undergoing a smooth localized threshold transition. The threshold induces correlated corrections to the inflaton and gauge sectors, including a Coleman-Weinberg term, a vacuum-polarization correction, and an anomaly-induced Chern-Simons coupling. Together, these effects transiently enhance and localize gauge-field production, generating a chiral stochastic gravitational-wave background in the deci-hertz band within the projected sensitivities of BBO and DECIGO, while remaining below representative primordial-black-hole bounds.

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Kai-Ge Zhang, Jian-Feng He, Chengjie Fu, Zong-Kuan Guo. 2026-04-15. Axion Inflation from Heavy-Fermion One-Loop Effects. https://arxiv.org/abs/2604.13674

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