Exact spontaneous plaquette ground states for high-spin ladder models
نویسندگان
چکیده
We study the exchange physics in high-spin Mott insulating systems with S=3/2 which is realizable in ultracold atomic systems. The high symmetry of SO 5 or SU 4 therein renders stronger quantum fluctuations than the usual spin-1 /2 systems. A spontaneous plaquette ground state without any site and bond spin orders is rigorously proved in a ladder spin-3 /2 model, whose topological excitations exhibit fractionalization behavior. The generalization to the SU N plaquette state is also investigated.
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