Formation of local moment near a static vacancy in the one-dimensional large-U Hubbard model

The effect of non-magnetic impurities in the one-dimensional large-U Hubbard model has been studied. For a single non-magnetic scatterer, it is shown that a bound state is obtained which is due to the singular behaviour of the T-matrix. It has been argued that the bound state which yields a delta-function density of states might correspond to local moment in the system giving rise to Curie-like contribution to the susceptibility. The spatial dependence of the impurity state wave function is shown to follow an algebraic decay. Its possible relevance to some recently discovered one-dimensional antiferromagnets has been discussed.