Critical behavior of metal-insulator transition in manganites

In 3-dimensional peroskite-type manganites RE(1-x)AE(x)MnO(3) (RE:trivalent rare earth ions, AE:divalent alkaline earth ions), the hydrostatic pressure enhances the double exchange (DE) interaction through the increase of the transfer integral, t. In terms of the increase of kinetic energy of carriers, such effect is quite similar to those of other perturbation such as the magnetic field, chemical pressure, carrier doping and so on. In this paper, the various IM transition induced by the hydrostatic pressure are shown and the analogy between the hydrostatic pressure and other external stimulus are discussed. Furthermore, the possibility of the critical state phase control in manganites by using the hydrostatic pressure is presented.