Formation of local moment near a static vacancy in the one-dimensional large-U Hubbard model
The Institute of Mathematical Sciences, Madras 600 113,
Accepted: 16 March 1998
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 δ-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.
PACS: 71.10.Fd – Lattice fermion models (Hubbard model, etc.) / 72.20.Dp – General theory, scattering mechanisms / 71.55.-i – Impurity and defect levels
© EDP Sciences, 1998