# Symmetry Breaking in Occupation Number Based Slave-Particle Methods

## TL;DR

This paper introduces a total-energy based method to enable symmetry breaking in occupation number slave-particle approaches, improving stability and efficiency in modeling strongly correlated electronic phases.

## Contribution

It presents a novel total-energy approach for inducing symmetry breaking in slave-particle methods, addressing previous difficulties and simplifying the self-consistent solution process.

## Key findings

- Enables spontaneous symmetry breaking in slave-particle models.
- Improves numerical stability and computational speed.
- Requires slave-particle models to explicitly include symmetry-breaking degrees of freedom.

## Abstract

We describe a theoretical approach for finding spontaneously symmetry-broken electronic phases due to strong electronic interactions when using recently developed slave-particle (slave-boson) approaches based on occupation numbers. We describe why, to date, spontaneous symmetry breaking has proven difficult to achieve in such approaches. We then provide a total-energy based approach for introducing auxiliary symmetry breaking fields into the solution of the slave-particle problem that leads to lowered total energies for symmetry broken phases. We point out that not all slave-particle approaches yield to energy lowering: the slave-particle model being used must explicitly describe the degrees of freedom that break symmetry. Finally, our total energy approach permits us to greatly simplify the formalism used to achieve a self-consistent solution between spinon and slave modes while increasing numerical stability and greatly speeding up the calculations.