Theoretical study on the spin and orbital orderings in Ruddlesden-Popper compound La3-3xCa1+3xMn3O10(0 ≤ x ≤ 1)

Abstract

In this paper, the spin and orbital orderings of the n = 3 Ruddlesden-Popper (RP) series of compounds La3-3xCa1+3xMn3O10 have been analyzed theoretically for the whole doping range 0 ≤ x ≤ 1, the calculation is based on the unrestricted Hartree-Fock approximation and the real-space recursion method. In agreement with experimental observations, we find that the ground state of La3-3xCa1+3xMn3O10 is ferromagnetic metal at x=0.3 and is G-type antiferromagnetic insulator at x = 1. The ferromagnetic metallic state is sustained for lower doping range 0 ≤ x 0.96. Our study unveils a strong spin-orbital correlation in the ferromagnetic metallic state for doping range 0 ≤ x < 0.39, an orbital ordering transition takes place at x = 0.06 which changes from the nearest-neighbor antiferro-orbital ordering (0 ≤ x < 0.06) to the layer-type antiferro-orbital ordering (0.06 < x < 0.39).