Spin dynamics of finite antiferromagnetic Heisenberg spin rings

摘要: The spin pair-correlation function of finite bipartite antiferromagnetic Heisenberg quantum rings was studied numerically by means exact diagonalization techniques. For large spins, the spectrum is a remarkably simple structure: It consists few characteristic peaks at low, and broad featureless signal high temperatures. This arises as energy exhibits set parallel rotational bands low energies emerging into quasi-continuum states, with transitions from lowest hand to being highly suppressed. hands can be accurately described generalized dispersion relation that depends on total number and, usual, shift number. These regularities are better fulfilled larger length but smaller ring size. will he shown all these features associated underlying sublattice structure rings, it argued they valid for more general class systems than rings.