Influence of a uniform magnetic field on dynamical chiral symmetry breaking in QED$_3$

TL;DR

This paper investigates how a uniform magnetic field influences dynamical chiral symmetry breaking in an effective QED3 model relevant to high-temperature cuprate superconductors, revealing that magnetic fields can induce a fermion gap and alter critical parameters.

Contribution

It demonstrates that a magnetic field can induce a dynamical fermion mass in QED3 and modifies critical flavor number and gap, providing new insights into magnetic effects in high-Tc superconductors.

Findings

Magnetic field induces a dynamical fermion gap above a critical strength.

Both critical flavor number and fermion gap increase with magnetic field.

Results can be tested in high-temperature cuprate superconductor experiments.

Abstract

We study dynamical chiral symmetry breaking (DCSB) in an effective QED$_{3}$ theory of d-wave high temperature cuprate superconductors under a uniform magnetic field. At zero temperature, the external magnetic field induces a mixed state by generating vortices in the condensate of charged holons. The growing magnetic field suppresses the superfluid density and thus reduces the gauge field mass which is opened via the Anderson-Higgs mechanism. By numerically solving the Dyson-Schwinger gap equation, we show that the massless fermions acquires a dynamical gap through DCSB mechanism when the magnetic field strength $H$ is above a critical value $H_{c}$ and the fermion flavors $N$ is below a critical value $N_{c}$. Further, it is found that both $N_{c}$ and the dynamical fermion gap increase as the magnetic field $H$ grows. It is expected that our result can be tested in phenomena in high temperature cuprate superconductors.