The elementary excitations of the ferromagnetic spin-orbital model which represents the low energy excitations for strongly correlated electrons described by the Hubbard Hamiltonian with a twofold-degeneracy are studied. For a completely degenerate system with the Ising-like orbital interactions the spin-and-orbital bound states can have much lower energy than the other excitations of the model and might thus be responsible for the instability of the ground state.
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