Describe how Make-Up work is obtained in Mr. Explain."- Presentation transcript:ġ Bellwork Identify two materials that you would need to get for Mr. Nonetheless, the slight reduction of LFMR in composites was attributed to the thick boundary layer created by NiO and impaired the spin polarised tunnelling process.Presentation on theme: "Bellwork Identify two materials that you would need to get for Mr. The magnetoresistance values of LCMO and its composites were found to increase monotonically with the decrease in temperature. The residual resistivity due to the grain/domain boundary is responsible for the scattering mechanism in the metallic region as suggested by the theoretical model fitting, r(T) = r0 + r2T2 + r4.5T4.5. The NiO nanoparticle acted as a barrier to charge transport and caused an increase in resistivity for composite samples. This further confirmed that there is no interfacial diffusion reaction between these two compounds. LCMO and NiO still retained their individual magnetic phase as observed from AC susceptibility (ACS) measurement. The microstructural analysis indicated the amount of NiO nanoparticles segregated at the grain boundaries or on the surface of LCMO grains increased with the increasing secondary phase content. The X-ray diffraction (XRD) patterns showed the coexistence of LCMO and NiO in the composites. The structural, microstructural, magnetic, electrical, and magneto-transport properties of (1□x) LCMO: x NiO, x = 0.00, 0.05, 0.10, 0.15 and 0.20 were investigated in detail. Polycrystalline La0.67Ca0.33MnO3 (LCMO) was prepared via the sol–gel route in this study. Incorporation of the secondary oxide phase into the manganite composite capable ofĮnhancing low-field magnetoresistance (LFMR) for viability in high-performance spintronic applications. This increase in MR at low temperature seems to be due to enhanced tunneling across PSMO grain boundaries and additional grain boundary effects introduced by NiO grains. This enhanced MR effect obviously comes through the formation of composites. This indicates that the MR ratio in the composites (up to x = 0.15) is larger than that in pure PSMO. So, the observed enhancement in MR at 80 K with respect to pure LSMO is ~3, ~6 and ~13 % for the composites with x = 0.05, 0.10 and x = 0.15, respectively, at 5 kOe field. The values of MR are large for the composites with x = 0.05, 0.10 and 0.15 and less for x = 0.20 as compared to pure PSMO (x = 0) at the temperature below 140 K. The temperature dependence of magnetoresistance (MR) in a field of 5 kOe for the composite samples is shown in Fig. This is due to the fact that the PM–FM phase transition is an intrinsic and intragrain property. The paramagnetic (PM) to ferromagnetic (FM) phase transition temperature (T C ) determined from the M-T curves (figure not shown here) is almost independent on the NiO content and is about ~253 K for all the samples. This successive decrease in M with increasing NiO concentrations is expected and is due to decrease in volume fraction of the ferromagnetic PSMO phase and increase in nonmagnetic NiO phase in the composites. that value of magnetization decreases with increasing NiO content. Inset shows the variation of MR (%) at 80 and 298 K with NiO content, x. Temperature dependence of MR of (PSMO) 1-x /(NiO) x composites.
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