Deconfined quantum critical points in fermionic systems with spin-charge separation

TL;DR

This paper uncovers new types of deconfined quantum critical points in fermionic systems with spin-charge separation, combining field theory analysis and numerical simulations to reveal partially gapped critical points beyond traditional paradigms.

Contribution

It introduces the concept of partially gapped deconfined quantum critical points in fermionic systems, supported by both theoretical and numerical evidence.

Findings

Identification of partially gapped deconfined quantum critical points

Field theory analysis of low-dimensional fermionic systems

Numerical derivation of gaps, order parameters, and correlation functions

Abstract

Deconfined quantum critical points are intriguing transition points not predicted by the Landau-Ginzburg-Wilson symmetry-breaking paradigm which are usually identified by the appearance of a continuous phase transition between locally ordered phases. Here, we reveal the presence of deconfined quantum critical points with unexplored properties. Contrary to previously known examples, we show that the phenomenon of spin-charge separation peculiar to interacting low dimensional fermions can allow for the appearance of partially gapped deconfined quantum critical points. We first infer this point by performing a field theory analysis of generic one-dimensional fermionic systems in the low energy limit. Subsequently, we derive a microscopic model where phase transitions between different locally ordered phases can take place. Here, by performing a numerical analysis we explicitly derive, among others, the gaps, local order parameters and correlation functions behavior, supporting the presence of partially gapped deconfined quantum critical points. Our results thus provide new interesting insights on the widely investigated topic of quantum phase transitions.