Charged Condensation

TL;DR

This paper explores a novel form of Bose-Einstein condensation involving charged scalars that results in unique electromagnetic properties, with potential implications for astrophysical objects and laboratory systems.

Contribution

It introduces the concept of charged scalar condensation with charge screening and Lorentz-violating photon mass, a new state of matter with distinctive gauge mode propagation.

Findings

Photon acquires Lorentz-violating mass in the condensate

Transverse and longitudinal modes propagate at different velocities

Charged condensate may form in high-density astrophysical environments

Abstract

We consider Bose-Einstein condensation of massive electrically charged scalars in a uniform background of charged fermions. We focus on the case when the scalar condensate screens the background charge, while the net charge of the system resides on its boundary surface. A distinctive signature of this substance is that the photon acquires a Lorentz-violating mass in the bulk of the condensate. Due to this mass, the transverse and longitudinal gauge modes propagate with different group velocities. We give qualitative arguments that at high enough densities and low temperatures a charged system of electrons and helium-4 nuclei, if held together by laboratory devices or by force of gravity, can form such a substance. We briefly discuss possible manifestations of the charged condensate in compact astrophysical objects.