One-Loop Charge-Breaking Minima in the Two-Higgs Doublet Model

TL;DR

This paper investigates the vacuum structure of the two-Higgs doublet model at one-loop level, revealing that charge-breaking vacua can be the global minimum, contrary to tree-level expectations.

Contribution

It demonstrates that one-loop corrections can alter the vacuum hierarchy, allowing charge-breaking minima to be energetically favored over charge-preserving ones.

Findings

Charge-breaking vacua can be the global minimum.

One-loop effects invalidate the tree-level theorem.

Explicit parameter sets show charge-breaking minima are deeper.

Abstract

We analyze the vacuum structure of the one-loop effective potential in the two Higgs doublet model. We find that electroweak-breaking vacuua can coexist with charge breaking ones, contradicting a theorem valid at tree-level. We perform a numerical analysis of the model and supply explicit parameter values for which charge-breaking vacuua can be the global minimum of the theory, and deeper than charge-preserving ones.