Magnetic ordering in a doped frustrated spin-Peierls system
Résumé
Based on a model of a quasi-one dimensional spin-Peierls system doped with nonmagnetic impurities, an effective two-dimensional Hamiltonian of randomly distributed S=1/2 spins interacting via long-range pairwise interaction is studied using a stochastic series expansion quantum Monte Carlo method. The susceptibility shows Curie-like behavior at the lowest temperatures reached although the staggered magnetisation is found to be finite for T-->0. The doping dependance of the corresponding three-dimensional Neel temperature is also computed