Structural, microstructural, transport, and magnetotransport properties of nanostructured La_0.7Sr_0.3MnO₃ manganites synthesized by coprecipitation

Abstract

The structural, transport, and magnetotransport properties of single-phase, homogeneous nanostructured La0.7Sr0.3MnO3 (LSMO) manganites synthesized by the coprecipitation route were investigated and the effect of sintering temperature on the microstructure of LSMO compounds was studied. A strong dependence of transport and magnetotransport behavior on the microstructure and nature of grain boundaries has been observed in the single-phase LSMO sintered at various temperatures. High-field magnetoresistance (HFMR) at room temperature is found to increase [13% (LS6) to 25% (LS9)] while low temperature (5 K) magnetoresistance decreases [75% (LS6) to 46% (LS9)] under 9 T field with increase in sintering temperature, which has been attributed to the spin-polarized tunneling and spin-dependent scattering of charge carriers.

Structural, transport and magnetic properties of monovalent doped La1−xNaxMnO3 manganites

“…Variation in exponent n indicates a continuous decrease with monovalent substitution which may be correlated with the increased hole density in La 1-x Na x MnO 3 manganites.To explore the magnetoresistance (MR) behavior of La 1-x Na x MnO 3 manganites, MR has been calculated using the formula: MR (%) = [(ρ H -ρ 0 ) / ρ 0 ] × 100 from ρ -T plots of LNMO samples.Fig.15shows MR vs. T plots under 1, 5 and 8T fields for LNMO samples. It can be seen that, all the samples exhibit appreciably large negative MR at low temperature ~ 5K (extrinsic contribution) and ~ T P (intrinsic contribution)[33,34]. Peak in MR (intrinsic MR) shifts towards higher temperature with increase in field which may be due to the field induced suppression in scattering of charge carriers at thegrain boundaries and Mn -O -Mn bonds leading to enhancement in transfer integral.…”

Structure and microstructure dependent transport and magnetic properties of sol–gel grown nanostructured La 0.6 Nd 0.1 Sr 0.3 MnO 3 manganites: Role of oxygen

“…Manganites have been studied in various forms such as polycrystalline bulk [4,6,7], nanostructures [16 -18], thin films [11 -13, 15], multilayers [3], heterostructures [5,8,9] and devices [14,19] for their transport and magnetotransport properties useful in various suitable practical applications such as bolometric applications, field and temperature sensors, p-n junctions, field form of bulk, thin films and nanostructures [15,17,20]. Also, rare earth ion substituted at La-site in La 0.7 Sr 0.3 MnO 3 (in the form of thin films, multilayers, heterostructures and nanostructured devices) has been studied in the form of nanostructured thin film devices [21,22], heterostructures [5,8,9], p-n junction devices [18,19] and multilayers [3,23] for their transport and magnetotransport properties.…”

“…Also, rare earth ion substituted at La-site in La 0.7 Sr 0.3 MnO 3 (in the form of thin films, multilayers, heterostructures and nanostructured devices) has been studied in the form of nanostructured thin film devices [21,22], heterostructures [5,8,9], p-n junction devices [18,19] and multilayers [3,23] for their transport and magnetotransport properties. Few reports are available on the studies on nanostructured La 0.7 Sr 0.3 MnO 3 manganite synthesized using sol-gel [24], citrate-gel [25], co-precipitation [17], etc.…”

Influence of Grinding Particle Size on Structure and Electrical Properties of La0.67Sr0.33MnO3−δCompound

“…Several studies have used these approaches to fabricate manganites with desired particle size [10][11][12]. However, the observed results of both electrical and magnetic properties showed remarkable discrepancies.…”