Polaron-mediated spin correlations in metallic and insulating La${}_{1-x}{A}_x$MnO${}_3$ ($A$=Ca, Sr, or Ba)

Abstract

Neutron spectroscopy measurements reveal short-range spin correlations near and above the ferromagnetic-paramagnetic phase transition in manganite materials of the form La${}_{1-x}{A}_x$MnO${}_3$, including samples with an insulating ground state as well as colossal magnetoresistive samples with a metallic ground state. Quasielastic magnetic scattering is revealed that forms clear ridges running along the [100]-type directions in momentum space. A simple model consisting of a conduction electron hopping between spin polarized Mn ions that becomes self-trapped after a few hops captures the essential physics of this magnetic component of the scattering. We associate this scattering component with the magnetic part of diffuse polarons, as we observe a temperature dependence similar to that of the diffuse structural scattering arising from individual polarons.

arXiv comment8 pages, 6 figures

References in corpus (20)

• Double Exchange Alone Does Not Explain the Resistivity of $L{a}_{1-x}S{r}_{x}Mn{O}_3$
• Complexity in Strongly Correlated Electronic Systems
• How to detect fluctuating order in the high-temperature superconductors
• Unconventional Ferromagnetic Transition in La1-xCaxMnO3
• Cooperative Jahn-Teller Effect and Electron-Phonon Coupling in $L{a}_{1-x}{A}_{x}Mn{O}_3$
• Colossal Effects in Transition Metal Oxides Caused by Intrinsic Inhomogeneities
• Phase instability induced by polar nanoregions in a relaxor ferroelectric system
• Hall-Effect Sign Anomaly and Small-Polaronic Conduction in (La_{1-x}Gd_x)_{0.67}Ca_{0.33}MnO_3
• Charge Ordering and Polaron Formation in the Magnetoresistive Oxide La0.7Ca0.3MnO3
• Short-range polaron correlations in the ferromagnetic La(1-x)Ca(x)MnO(3)
• Charge melting and polaron collapse in $L{a}_{1.2}S{r}_{1.8}M{n}_2{O}_7$
• Evolution of the low-frequency spin dynamics in ferromagnetic manganites
• Orbital order induced metal-insulator transition in (La,Ca)MnO3
• Intrinsic chemical and structural inhomogeneity in lightly doped La(1-x)Sr(x)MnO(3)
• First-order nature of the ferromagnetic phase transition in (La-Ca)MnO_3 near optimal doping
• Spin dynamics of strongly-doped La_{1-x}Sr_xMnO_3
• Coexistence and competition of local- and long-range polar orders in a ferroelectric relaxor
• Magnons in Ferromagnetic Metallic Manganites
• Large lattice distortions associated with the magnetic transition in La0.7Sr0.3MnO3
• Paramagnetic Spin Correlations in Colossal Magnetoresistive La0.7Ca0.3MnO3

Cited by in corpus (4)

• Spin wave damping arising from phase coexistence below $T_c$ in colossal magnetoresistive La${}_{0.7}$Ca${}_{0.3}$MnO${}_3$
• Damping and softening of transverse acoustic phonons in colossal magnetoresistive La${}_{0.7}$Ca${}_{0.3}$MnO${}_3$ and La${}_{0.7}$Sr${}_{0.3}$MnO${}_3$
• Interacting chains of orbital polarons in "Colossal" magnetoresistive La1-xSrxMnO3 revealed by spin and lattice dynamics
• Far- and Mid-infrared Emission and Reflectivity of Orthorhombic and Cubic ErMnO3: polarons and bipolarons