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International audienceThe structural, magnetic and electrical properties of (La0.70−xNdx)Sr0.30Mn0.70Ti0.30 O 3 perovskites (0 ≤ x ≤ 0.30) prepared by the usual ceramic procedure were investigated. Structural Rietveld refinements of the X-ray powder diffraction revealed that for x = 0 the compound crystallizes in a rhombohedral (R 3¯ c) perovskite structure, while for x = 0.10, 0.20 and 0.30 the structure becomes orthorhombic (Pbnm). The field-cooled, zero-field-cooled and M(H) measurements lead to conclude that the samples with x≥0.10 behave like spin-glass systems. The temperature dependence of the resistivity exhibits two transitions at two temperatures T p1 and T p2, with the same width for the two peaks. T P1 results from the competition between double-exchange and super-exchange mechanisms inside the grain (intrinsic effects) whereas T P2 arises due to the grain boundary effects (extrinsic effect). The resistivity of this system seems to be related to the competition between antiferromagnetic insulating (AFI) phases, ferromagnetic insulating (FMI) phases and ferromagnetic metal (FMM) phases, which is induced by Nd doping effect

In this paper, four SPR sensors have been proposed and analyzed theoretically. The proposed SPR sensors are prism—Au-Ag alloy—CH3NH3PbI3—Au-Ag alloy—graphene—sensing medium, prism—Au-Al alloy—CH3NH3PbI3—Au-Al alloy—graphene—sensing medium, prism—CH3NH3PbI3—Au-Ag alloy—CH3NH3PbI3—graphene—sensing medium and prism—CH3NH3PbI3—Au-Al alloy—CH3NH3PbI3—graphene—sensing medium. Matrix method for N-layer model has been utilized to analysis the performance parameters of the proposed sensors. The performance parameters were determined in terms of the detection accuracy (DA), sensitivity, and figure of Merit (FoM). The thicknesses of bimetallic alloy and CH3NH3PbI3 layers and bimetallic alloy composition have been optimized to achieve the best performance of the sensors. It is found that the best detection accuracy, sensitivity and figure of Merit of the proposed sensors are 0.279 deg−1, 85.2 deg/RIU and 23.79 RIU−1 for configuration I; 0.414 deg−1, 77.2 deg/RIU and 32.03 RIU−1 for configuration II; 0.120 deg−1, 106.60 deg/RIU and 12.81 RIU−1 for configuration III; and 0.186 deg−1, 93 deg/RIU and 17.35 RIU−1 for configuration IV.

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