Rank-2 $U(1)$ spin liquid on the breathing pyrochlore lattice

Understand

Higher-rank generalisations of electrodynamics have recently attracted considerable attention because of their ability to host "fracton" excitations, with connections to both quantum stabilizer codes and holography.

• However, the search for higher-rank gauge theories in experiment has been greatly hindered by the lack of materially-relevant microscopic models.
• Here we show how a spin liquid described by rank-2 $U(1)$ gauge theory can arise in a magnet on the breathing pyrochlore lattice.
• We identify Yb-based breathing pyrochlores as candidate systems, and make explicit predictions for how the rank-2 $U(1)$ spin liquid would manifest itself in experiment.