Low-Temperature Permittivity of Insulating Perovskite Manganites

Abstract

Measurements of the low-frequency (f<=100 kHz) permittivity and conductivity at T<= 150 K are reported for La(1-x)Ca(x)MnO(3) (0<=x<=1) and Ca(1-y)Sr(y)MnO(3) (0<=y<=0.75) having antiferromagnetic, insulating ground states covering a broad range of Mn valencies from Mn(3+) to Mn(4+). Static dielectric constants are determined from the low-T limiting behavior. With increasing T, relaxation peaks associated with charge-carrier hopping are observed in the real part of the permittivities and analyzed to determine dopant binding energies. The data are consistent with a simple model of hydrogenic impurity levels and imply effective masses m*/m_e~3 for the Mn(4+) compounds. Particularly interesting is a large dielectric constant (~100) associated with the C-type antiferromagnetic state near the composition La(0.2)Ca(0.8)MnO(3).

6 pages, 8 figures, PRB in press

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Cited by in corpus (22)

• Colossal dielectric constants in transition-metal oxides
• Colossal dielectric constant up to GHz at room temperature
• Magnetodielectric consequences of phase separation in the colossal magnetoresistance manganite Pr0.7Ca0.3MnO3
• Emergent nanoscale superparamagnetism at oxide interfaces
• Polaron relaxation and hopping conductivity in LaMn${}_{1-x}$Fe${}_x$O${}_3$
• Finite size and intrinsic field effect on the polar-active properties of the ferroelectric-semiconductor heterostructures
• Direct Observation of an Interface Dipole between Two Metallic Oxides Caused by Localized Oxygen Vacancies
• Impurity Conduction and Magnetic Polarons in Antiferromagnetic Oxides
• Polaron Transport in the Paramagnetic Phase of Electron-Doped Manganites
• Doping Dependence of Polaron Hopping Energies in La(1-x)Ca(x)MnO(3) (0<= x<= 0.15)
• Polar catastrophe, electron leakage, and magnetic ordering at the LaMnO${}_3$/SrMnO${}_3$ interface
• Intragrain electrical inhomogenities and compositional variation of static dielectric constant in LaMn_{1-x}Fe_xO_3
• Dielectric anomaly at the orbital order-disorder transition in LaMnO_(3+delta)
• Dielectric anomaly at T_N in LaMnO3
• Hopping dynamics of interacting polarons
• Giant electro-thermal conductivity and spin-phonon coupling in an antiferromagnetic oxide
• Electronic and Magnetic Reconstructions in Manganite Superlattices
• Glassy dielectric anomaly and negative magneto-capacitance effect in electron-doped Ca${}_{1-x}$Sr${}_x$Mn${}_{0.85}$Sb${}_{0.15}$O${}_3$
• High On/Off Ratio Memristive Switching of Manganite-Cuprate Bilayer by Interfacial Magnetoelectricity
• Competing `soft' dielectric phases and detailed balance in thin film manganites
• Anisotropic In-Plane Strain and Transport in Epitaxial Nd(0.2)Sr(0.8)MnO(3) Thin Films
• Electrical transport properties of manganite powders under pressure