https://doi.org/10.1140/epjc/s10052-019-6604-z
Regular Article - Theoretical Physics
Asymptotic freedom in 
-Yukawa-QCD models
1
Theoretisch-Physikalisches Institut, Friedrich-Schiller-Universität Jena, 07743, Jena, Germany
2
Abbe Center of Photonics, Friedrich-Schiller-Universität Jena, 07743, Jena, Germany
3
Helmholtz-Institut Jena, Fröbelstieg 3, 07743, Jena, Germany
* e-mail: rene.sondenheimer@uni-jena.de
Received:
22
May
2018
Accepted:
17
January
2019
Published online:
31
January
2019
-Yukawa-QCD models are a minimalistic model class with a Yukawa and a QCD-like gauge sector that exhibits a regime with asymptotic freedom in all its marginal couplings in standard perturbation theory. We discover the existence of further asymptotically free trajectories for these models by exploiting generalized boundary conditions. We construct such trajectories as quasi-fixed points for the Higgs potential within different approximation schemes. We substantiate our findings first in an effective-field-theory approach, and obtain a comprehensive picture using the functional renormalization group. We infer the existence of scaling solutions also by means of a weak-Yukawa-coupling expansion in the ultraviolet. In the same regime, we discuss the stability of the quasi-fixed point solutions for large field amplitudes. We provide further evidence for such asymptotically free theories by numerical studies using pseudo-spectral and shooting methods.
© The Author(s), 2019
