Chimeric states of matter: Meissner effect without superconductivity

TL;DR

This paper introduces chimeric states of matter where features of symmetry-broken and symmetry-restored phases coexist, showing that the Meissner effect can occur without superconductivity, broadening the understanding of phases of matter.

Contribution

It presents the concept of chimeric states of matter, demonstrating that the Meissner effect can exist in resistive or insulating media and proposing Josephson junction networks as a potential experimental realization.

Findings

Meissner effect can occur without superconductivity

Chimeric states involve coexistence of broken and unbroken symmetry features

Effective field theory of symmetry chimerization developed

Abstract

Symmetry is central to how we classify phases of matter: solids break spatial translations, superfluids break particle-number conservation, and superconductors "break" gauge symmetry. Mixed anomalies involving higher-form symmetries, however, present a generalization of spontaneous symmetry breaking that admits a wider and more versatile set of possibilities. We introduce chimeric states of matter, in which aspects of broken and unbroken phases coexist. We find that the Meissner effect -- usually regarded as the defining hallmark of superconductivity -- can occur in media that are resistive or even insulating when probed by electric fields. We demonstrate this by constructing an effective field theory of "symmetry chimerization" and propose that Josephson junction networks could provide a laboratory realization. These results broaden the landscape of possible phases of matter, showing that physical media can mix features of symmetry-restored and symmetry-broken states in a single substrate.