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تسجيل مستخدم جديدAbelian flux induced magnetic frustrations of spinor boson superfluids on a square lattice
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Inspired by recent experimental advances to generate Abelian flux for neutral cold atoms and photons moving in a lattice, we investigate the possible effects of the $ pi $ flux through a unit cell in the pseudo-spin 1/2 spinor boson Hubbard model in a square lattice. We find that the $ pi $ flux induces a dramatic interplay between the charge and the spin which leads to a frustrated superfluid. We develop a new and systematic order from quantum disorder analysis to determine not only the true quantum ground state, but also the excitation spectrum. The superfluid ground state has a 4 sublattice $ 90^{circ} $ coplanar spin structure which supports 4 linear gapless modes with 3 different velocities. We speculate the transition from the weak coupling frustrated SF to the strong coupling Ferromagnetic Mott state to be in a new universality class of non-Ginsburg Landau type. These novel phenomena may be observed in these recent cold atom and photonic experiments.
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