Date of Original Version
The exact one-to-one mapping between (spinless) Jordan–Wigner lattice fermions and (spin-1/2) spinons is established for all eigenstates of the one-dimensional s = 1/2 XX model on a lattice with an even or odd number N of lattice sites and periodic boundary conditions. Exact product formulae for the transition rates derived via Bethe ansatz are used to calculate asymptotic expressions of the 2-spinon and 4-spinon parts (for large even N) as well as of the 1-spinon and 3-spinon parts (for large odd N) of the dynamic spin structure factors. The observability of these spectral contributions is assessed for finite N and for N → ∞.
M. Arikawa, M. Karbach, G. Müller, and K. Wiele. Spinon excitations in the XX chain:spectra, transition rates, observability. Journal of Physics A, 39 (2006), 10623-10640.
Available at: http://dx.doi.org/10.1088/0305-4470/39/34/002