The vacuum structure of the Higgs complex singlet-doublet model

TL;DR

This paper explores the complex vacuum landscape of the Higgs complex singlet-doublet model, analyzing its multiple minima and implications for vacuum stability in theories addressing dark matter and baryogenesis.

Contribution

It provides a detailed analysis of the seven possible minima in the scalar potential and discusses the conditions for vacuum stability and tunneling in this model.

Findings

Seven types of minima identified at tree-level.

Conditions for vacuum coexistence and tunneling analyzed.

Implications for dark matter and baryogenesis models discussed.

Abstract

The complex singlet-doublet model is a popular theory to account for dark matter and electroweak baryogenesis, wherein the Standard Model particle content is supplemented by a complex scalar gauge singlet, with certain discrete symmetries imposed. The scalar potential which results thereof can have seven different types of minima at tree-level, which may coexist for specific choices of parameters. There is therefore the possibility that a given minimum is not global but rather a local one, and may tunnel to a deeper extremum, thus causing vacuum instability. This rich vacuum structure is explained and discussed in detail.