Suppression of ferromagnetic ordering in doped manganites: Effects of the superexchange interaction

Abstract

From a Monte Carlo study of the ferromagnetic Kondo lattice model for doped manganites, including the antiferromagnetic superexchange interaction ($J_{AF}$), we found that the ferromagnetic ordering was suppressed as $J_{AF}$ increased. The ferromagnetic transition temperature $T_c$, as obtained from a mean field fit to the calculated susceptibilities, was found to decrease monotonically with increasing $J_{AF}$. Further, the suppression in $T_c$ scales with the bandwidth narrowing induced by the antiferromagnetic frustration originating from $J_{AF}$. From these results, we propose that the change in the superexchange interaction strength between the $t_{2g}$ electrons of the Mn ions is one of the mechanisms responsible for the suppression in $T_c$ observed in manganites of the type (La${}_{0.7-y}$Pr${}_y$)Ca${}_{0.3}$MnO${}_3$.

arXiv comment5 pages, 6 figures. To appear in PRB

References in corpus (5)

• Double Exchange Alone Does Not Explain the Resistivity of $L{a}_{1-x}S{r}_{x}Mn{O}_3$
• Dynamic Jahn-Teller Effect and Colossal Magnetoresistance in $L{a}_{1-x}{A}_{x}Mn{O}_3$
• Phase Separation in Electronic Models for Manganites
• Static and Dynamical Properties of the Ferromagnetic Kondo Model with Direct Antiferromagnetic Coupling Between the localized $t_{2g}$ Electrons
• Optical conductivity of colossal magnetorestistance compounds: Role of orbital degeneracy in the ferromagnetic phase

Cited by in corpus (7)

• Magnetic relaxation phenomena and cluster glass properties of La{0.7-x}Y{x}Ca{0.3}MnO{3} manganites
• Orbital ordering phenomena in $d$- and $f$-electron systems
• Reentrant spin glass transition in La${}_{0.96-y}$Nd${}_y$K${}_{0.04}$MnO${}_3$: origin and effects on the colossal magnetoresistivity
• Anomalous spin susceptibility and magnetic polaron formation in the double exchange systems
• Spin wave dispersion softening in the ferromagnetic Kondo lattice model for manganites
• Suppression and revival of long-range ferromagnetic order in the multiorbital Fermi-Hubbard model
• Role of the superexchange interaction in magnetic transition and polaron crossover