Large-$N$ SU(4) Schwinger boson theory for coupled-dimer antiferromagnets

Shang-Shun Zhang, Yasuyuki Kato, E. A. Ghioldi +3

We develop a systematic large-$N$ expansion based on the Schwinger boson representation of SU(4) coherent states of dimers for the paradigmatic spin-$1/2$ bilayer square lattice He…