Chemical Pressure Tuning of Magnetic Coupling in the La1.4Sr1.6Mn2O7 Bilayered Manganite

In this paper the effect of the chemical pressure induced by the Sr replacement for Ca in the La1.4Sr1.6Mn2O7 lattice is directly probed by means of neutron diffraction as a function of temperature. The results show a progressive change of the magnetic coupling from ferromagnetic to antiferromagnetic by increasing the Ca content,. indicating that the orbital order of the Mn ions is affected in the same way by the application of an external pressure and by the chemical pressure.