By using a set of gauge transformations, the exact solutions of the XXZ spin
chain with unparallel boundary magnetic fields are derived in the framework of
the algebraic Bethe ansatz. In the ...easy-plane case, we show the elementary
excitations are some kind of spinons without definite spin because the U(1)
symmetry is broken, while in the easy-axis ferromagnetic case a spiral state is
realized in the ground state. The correlation functions, the spin torque as
well as the spin voltage for the later case are also derived.
By using a set of gauge transformations, the exact solutions of the XXZ spin chain with unparallel boundary magnetic fields are derived in the framework of the algebraic Bethe ansatz. In the ...easy-plane case, we show the elementary excitations are some kind of spinons without definite spin because the U(1) symmetry is broken, while in the easy-axis ferromagnetic case a spiral state is realized in the ground state. The correlation functions, the spin torque as well as the spin voltage for the later case are also derived.
