Magnetic order and moment distribution in doped spin-chain systems

Artikel i vetenskaplig tidskrift, 2004

We consider the effect of doping on the magnetic order in quasi one-dimensional (1D) antiferromagnets. First the detailed magnetic response of nite spin-1 2 chains in the presence of a staggered eld is determined, which by itself shows an interesting crossover as function of length and eld strength. We can then understand the ordering by including an effective coupling between the chains, which results in a N!eel-ordered phase at low temperatures, but with a broad distribution of magnetic moments that has to be determined self-consistently.