Anomaly-Induced Magnetic Screening in 2+1 dimensional QED at Finite Density

TL;DR

This paper demonstrates that in 2+1 dimensional QED at finite density, an external magnetic field is screened due to an anomaly, leading to a Meissner effect, with significant physical implications.

Contribution

It reveals that the axial anomaly causes magnetic screening in 2+1D QED at finite density, a novel insight into anomaly-induced phenomena.

Findings

Magnetic field is screened in 2+1D QED at finite density.

The screening is due to a 2D axial anomaly.

This leads to a Meissner effect in the system.

Abstract

We show that in 2+1 dimensional Quantum Electrodynamics an external magnetic field applied to a finite density of massless fermions is screened, due to a $2+1$-dimensional realization of the underlying $2$-dimensional axial anomaly of the space components of the electric current. This is shown to imply screening of the magnetic field, i.e., the Meissner effect. We discuss the physical implications of this result.