Spontaneous electromagnetic superconductivity of vacuum in strong magnetic field: evidence from the Nambu--Jona-Lasinio model

TL;DR

This paper demonstrates that in extremely strong magnetic fields, the vacuum can spontaneously become an electromagnetic superconductor due to quark-antiquark condensates, revealing a novel phase of empty space with vortex structures.

Contribution

It provides evidence from the Nambu--Jona-Lasinio model that vacuum superconductivity occurs under strong magnetic fields, a phenomenon not present in pure QED.

Findings

Vacuum becomes superconducting above 10^{16} Tesla

Superconductivity involves quark-antiquark vector condensates

The phase features vortex structures similar to Abrikosov lattices

Abstract

Using an extended Nambu--Jona-Lasinio model as a low--energy effective model of QCD, we show that the vacuum in a strong external magnetic field (stronger than 10^{16} Tesla) experiences a spontaneous phase transition to an electromagnetically superconducting state. The unexpected superconductivity of, basically, empty space is induced by emergence of quark-antiquark vector condensates with quantum numbers of electrically charged rho mesons. The superconducting phase possesses an anisotropic inhomogeneous structure similar to a periodic Abrikosov lattice in a type-II superconductor. The superconducting vacuum is made of a new type of vortices which are topological defects in the charged vector condensates. The superconductivity is realized along the axis of the magnetic field only. We argue that this effect is absent in pure QED.