Effect of Multiple Higgs Fields on the Phase Structure of the SU(2)-Higgs Model

TL;DR

This study investigates how multiple Higgs fields influence the phase structure of the SU(2)-Higgs model, revealing that multiple fields can disconnect the Higgs and confinement regions, unlike the single-field case.

Contribution

It demonstrates that multiple Higgs fields alter the phase diagram, preventing the analytic connection between phases seen with a single Higgs field, and explores the effects of asymmetry in Higgs couplings.

Findings

Multiple Higgs fields break the analytic connection between phases.

Asymmetry in Higgs couplings can enhance phase transition effects.

No direct coupling between different Higgs flavors is assumed.

Abstract

The SU(2)-Higgs model, with a single Higgs field in the fundamental representation and a quartic self-interaction, has a Higgs region and a confinement region which are analytically connected in the parameter space of the theory; these regions thus represent a single phase. The effect of multiple Higgs fields on this phase structure is examined via Monte Carlo lattice simulations. For the case of N>=2 identical Higgs fields, there is no remaining analytic connection between the Higgs and confinement regions, at least when Lagrangian terms that directly couple different Higgs flavours are omitted. An explanation of this result in terms of enhancement from overlapping phase transitions is explored for N=2 by introducing an asymmetry in the hopping parameters of the Higgs fields. It is found that an enhancement of the phase transitions can still occur for a moderate (10%) asymmetry in the resulting hopping parameters.