Renormalization group analysis of competition between distinct order parameters

TL;DR

This paper uses renormalization group analysis to show that competition between different order parameters in a (2+1)-D quantum field theory leads to the absence of stable fixed points, causing continuous transitions to become first-order.

Contribution

It provides a detailed RG analysis demonstrating that competing order parameters prevent stable fixed points, turning continuous phase transitions into first-order transitions.

Findings

No stable fixed points in the RG flow.

Continuous transitions become first-order due to competition.

Massless Goldstone bosons influence ordering competition.

Abstract

We perform a detailed renormalization group analysis to study a (2+1)-dimensional quantum field theory that is composed of two interacting scalar bosons, which represent the order parameters for two continuous phase transitions. This sort of field theory can describe the competition and coexistence between distinct long-range orders, and therefore plays a vital role in statistical physics and condensed matter physics. We first derive and solve the renormalization group equations of all the relevant physical parameters, and then show that the system does not have any stable fixed point in the lowest energy limit. Interestingly, this conclusion holds in both the ordered and disordered phases, and also at the quantum critical point. Therefore, the originally continuous transitions are unavoidably turned to first-order due to ordering competition. Moreover, we examine the impacts of massless Goldstone boson generated by continuous symmetry breaking on ordering competition, and briefly discuss the physical implications of our results.