Green’s function method applied to the paramagnetic properties of R_1−xX_xMnO₃

Abstract

The magnetic properties of the isotropic manganites R(1-x)X(x)MnO(3) are studied in the paramagnetic regime using the Green's function method. The Curie-Weiss and critical temperatures, Θ and T(c), are obtained within the random phase approximation, as well as the high-temperature susceptibility. Our results are in agreement with other theoretical and experimental results.

The three-dimensional mixed-spin Heisenberg model applied to the magnetic properties of La1−xSrxMnO3 in the random phase approximation

“…It has also been shown in the experiment and theory that 22,29 the DE interaction may be well represented in terms of the simple two sites Mn 3+ -Mn 4+ Heisenberg interaction for doping 0.15Ͻ x Ͻ 0.5. As the microscopic modeling of doped manganites shows, 23 CMR manganites are characterized by a complex interplay of charge, spin, orbital, and lattice degrees of freedom.…”

“…13 A simplified model for this interaction 22,29 indicates that the hopping of electrons between Mn ions connects them, forming high spin magnetic clusters that include the itinerant electron. 13 A simplified model for this interaction 22,29 indicates that the hopping of electrons between Mn ions connects them, forming high spin magnetic clusters that include the itinerant electron.…”