Effects of ferroelectric-poling-induced strain on the transport and magnetic properties of La7/8Ba1/8MnO3 thin films

Abstract

We have investigated the effects of the strain induced by ferroelectric poling on the transport and magnetic properties of La 7/8 Ba 1/8 MnO 3 ͑LBMO͒ thin films epitaxially grown on ferroelectric 0.67Pb͑Mg 1/3 Nb 2/3 ͒O 3 -0.33PbTiO 3 ͑PMN-PT͒ single-crystal substrates. The ferroelectric poling reduces the in-plane tensile strain of the film, giving rise to a decrease in the resistivity and an increase in the magnetization, Curie temperature, and magnetoresistance of the LBMO film. These strain effects are explained within the framework of coexisting phases whose volume fractions are modified as a result of the reduction in the tetragonal distortion of MnO 6 octahedra induced by ferroelectric poling. An investigation of the effects of polarization reversal on the transport properties of the LBMO film indicates that the ferroelectric-poling-induced strain effects dominate over the ferroelectric field effects in the LBMO/PMN-PT structure.

Interface strain coupling and its impact on the transport and magnetic properties of LaMnO3 thin films grown on ferroelectrically active substrates

“…For example, at H = 9 T associated with the poling of the substrate, the MR at T = 170, 230, and 300 K was enhanced by ∼22.2%, 13.7%, and 11%, respectively, indicating that the lower the temperature, the larger the effects of the induced strain on the MR. This strain-induced enhancement of MR is similar to that observed in the La 7/8 Ba 1/8 MnO 3 films grown on PMN-PT substrates [26], implying that the underlying mechanism responsible for the enhancement of MR is probably the same as that in the La 7/8 Ba 1/8 MnO 3 /PMN-PT structure. Namely, the effects of the induced strain on MR are closely related to the strain-induced change in the volume fraction of coexisting paramagnetic and ferromagnetic phases.…”

“…At high temperatures (T > 118 K), although short range FM ordering within FM clusters is not established, a small fraction of FM clusters may still exist because of local Mn 3+ -O-Mn 4+ DE interaction. Associated with the increase in the electronic bandwidth and the suppression of the JT distortion induced by the poling of the PMN-PT substrate, the volume fraction of the FM clusters would increase while that of the PM insulating matrix would decrease [26]. As a result, the MR for the P + r state is larger than that for the P r 0 state due to enhanced volume fraction of FM clusters.…”

Polycrystalline La0.66Gd0.04Ca0.3MnO3 for magnetic-response applications: concurrent anisotropic magnetoresistance and magneto-transport under a low magnetic field

“…In this regard, several strategies for increasing the resistivity versus temperature ( ρ – T ) relationship, particularly among the M–I competing transitions, have been proposed in the literature to enhance the magnetic and electrical characteristics of manganites. These approaches include the controllable incorporation of dopant elements as occupancy ions, 10 the application of external electric stimuli 11 or the magnetic field modulations, 12 and the employment of modified synthesis procedures. 13 Consequently, doping-induced lattice distortion in manganites provides multiple avenues for tuning the double-exchange (DE) interaction 14 and enhancing the magneto-electronic functions, like MR and TCM.…”

The investigation of reversible strain and polarization effect in (011)-La0.9Ba0.1MnO3 film using field effect configuration

“…7 By applying dc electric fields across ferroelectric crystal and dynamically tuning the strain state, Zheng et al also reported that the ferroelectric-poling-induced strain reduction gives rise to a decrease in the resistivity and an increase in Curie temperature, ferromagnetism, and magnetoresistance of (001)-oriented La 0.875 Ba 0.125 MnO 3 film. 8 On the other hand, the polarization effect should be taken into account since a ferroelectric substrate is used in such investigations. Wu 11 These results indicate the field-induced polarization effect should also be considered in the studies of the field-induced strain effect and deserves to be investigated carefully.…”