Dynamics of the lattice and spins in the phase-separated manganite (Eu${}_{1-x}$Gd${}_x$)${}_{0.6}$Sr${}_{0.4}$MnO${}_3$

Abstract

We investigated slow relaxations of the magnetostriction and residual magnetostriction of the phase-separated system (Eu${}_{1-x}$Gd${}_x$)${}_{0.6}$Sr${}_{0.4}$MnO${}_3$, in which the metamagnetic transition from a paramagnetic insulating state to a ferromagnetic metallic state is accompanied by a lattice shrinkage. The relaxations are well fitted by a stretched exponential function, suggesting the strong frustraction between the double exchange interaction and Jahn-Teller effect. We have revealed that the Gd substitution suppresses the frozen phase-separated phase at low temperatures and stabilizes the paramagnetic insulating state in the dynamic phase-separated phase at intermediate temperatures. The former origin would be the randomness effect and the latter would be the suppression of the double exchange interaction.

6 pages. 6 figures

References in corpus (2)

• Steplike Lattice Deformation of Single Crystalline (La${}_{0.4}$Pr${}_{0.6}$)${}_{1.2}$Sr${}_{1.8}$Mn${}_2$O${}_7$ Bilayered Manganite
• Anomalous pressure effect on the remanent lattice striction of a (La,Pr)${}_{1.2}$Sr${}_{1.8}$Mn${}_2$O${}_7$ bilayered manganite single crystal