Suppression of the ferromagnetic-insulating phase in self-dopedLa0.94Mn0.98O3crystals under pressure

The effect of hydrostatic pressure P on the magnetic and transport properties of self-doped ${\mathrm{La}}_{0.94}{\mathrm{Mn}}_{0.98}{\mathrm{O}}_3$ crystals has been investigated at pressures up to 1 GPa and in the temperature range $15<T<\mathrm{}300\mathrm{}\mathrm{K}.$ It was found that the applied pressure enhances the double-exchange coupling, increases the magnetization, and lowers the ferromagnetic-insulator transition temperature. The results obtained here for the self-doped crystals are compared with those observed for lightly doped ${\mathrm{La}}_{1-x}{\mathrm{Sr}}_x{\mathrm{MnO}}_3.$ It is shown that similar mechanisms of ferromagnetic clustering and percolative polarons may account also for the magnetic and transport properties of the self-doped manganites.