Studies of the spin diffusion coefficient and the spin stiffness constant for the t J model on low-dimensional lattices and possible application to doped antiferromagnets
The spin response functions for a doped strongly correlated quantum Heisenberg antiferromagnet, in the form of a t-J model, on low-dimensional lattices have been explored. In particular, the spin stiffness constant and the spin diffusion coefficient have been calculated as functions of doping concentration by different approaches for this model on a chain and on a square lattice. The occurrences of various possible magnetic phases, namely with long range and short range orders, and also a novel paramagnetic phase, have been predicted at zero temperature. Our conclusions regarding the phase diagram agree remarkably well with those from other recent theoretical approaches. Our results are discussed in the light of experimental results from the cuprates.