A family of affine quantum group invariant integrable extensions of the Hubbard Hamiltonian Original Research Article

We construct a family of spin chain Hamiltonians, which have the affine quantum group symmetry Uqĝ. Their eigenvalues coincide with the eigenvalues of the usual spin chain Hamiltonians, but have the degeneracy of levels, corresponding to the affine Uqĝ. The space of states of these spin chains is formed by the tensor product of the fully reducible representations of the quantum group.