Magnetic correlation length in oxide superconductors

Abstract

We have used a self-consistent theory based on the quasi-two dimensional Heisenberg model to explain the magnetic correlation length for both undoped and doped samples of La 2 CuO 4− χ . We have used the self-consistent Green's function approach to find an analytical expression for the magnetic correlation length. Our analytical expression gives an exponential decay of correlation length with temperature and it includes the effect of doping through it's dependence over the interlayer coupling. We have compared our numerical calculations for magnetic correlation length with experiments. A good agreement between our theory and experimental results is achieved. We have also compared our numerical results for the undoped material with other theoretical results.