Short-range polaron correlations in the ferromagnetic La1-xCaxMnO3

We use neutron scattering to demonstrate the presence of lattice polarons and their short-range correlations for several samples of La1-xCaxMnO3 in the Ca doping range 0.15</=x</=0.3. We establish the doping dependence of the orientation, commensuration, and coherence length of the polaron correlations and show that the populations of correlated and uncorrelated polarons are intimately related to the transport properties of the materials.