In this article, we have studied the changes in structural, magnetic, and magneto-transport properties of Bi2Te3 topological insulator doped with magnetic (Fe) as well as non-magnetic (In) elements. The un-doped along with Fe, In-doped Bi2Te3 are grown using a melt growth technique. The Rietveld analysis of x-ray diffraction data expresses that both In and Fe-dopants substituted the Bi-position with a little bit of interstitial incorporation in host Bi2Te3. It is also noticed that In-doping is slightly favorable for Bi-substitution than Fe. The magnetic characterization reveals a mixing of diamagnetic and Pauli paramagnetic behavior of un-doped and In-doped Bi2Te3, whereas, Fe-doping shows overall paramagnetism with local anti-ferromagnetic interactions among Fe-ions without long-range order. Electrical-transport study represents the metallic response of host Bi2Te3, which is well-maintained for In-doping; however, Fe-doping exhibits prominent anomalies in ρ_xx –T profiles. Importantly, magneto-conductance research indicates a notable deviation of host quantum feature, weak anti-localization effect (WAL) upon magnetic (Fe) doping, whereas non-magnetic In-doping shows a comparatively weak deviation in WAL effect for high doping limit.

The performance of the spintronic devices is highly dependent on spin polarization. Here, we have performed the first-principles DFT calculation for L21-ordered and B2-disordered Co2FeSi Heusler alloys along with the effect of lattice strain on spin polarization. In both cases, the spin polarization decreases, but the total magnetic moment increases. For experimental study, Co2FeSi/SiO2/p-Si heterostructures have been fabricated by growing codeposited Co2FeSi film on p-type silicon. Experimentally, we demonstrate the accumulation of spin-polarized carriers in p–Si from B2-ordered half-metal Co2FeSi film by measuring magnetic field-dependent electrical transport properties of the device using self-formed SiO2 as a tunnel barrier. Magnetic field-dependent current (I)–voltage (V) behavior of the device shows a prominent spin-valve effect at low temperature. Spin polarization of the device has been calculated by measuring the current across the heterostructure in the presence of a magnetic field.

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We have investigated the in-plane and out-of-plane magnetostriction (λ) and strain sensitivity [Formula: see text] of the polycrystalline ZnFe2O4 (ZFO) film on an Si(100) substrate at room temperature using the optical cantilever beam magnetometer. A remarkable enhancement in magnetostriction (129.34%) and strain sensitivity (218.49%) is obtained in the out-of-plane configuration in comparison with the same in the in-plane configuration. The film possesses a high positive magnetostriction (strain sensitivity) of 325.67 ± 0.42 ppm [Formula: see text] and 746.92 ± 1.18 ppm [Formula: see text] for in-plane and out-of-plane geometry, respectively, at room temperature. The huge enhancement in magnetostriction and strain sensitivity is ascribed to the shape anisotropy of the ZFO/Si composite in the out-of-plane configuration, and thus, the out-of-plane configuration would be highly potential in designing magnetic actuators, magnetic memory devices, and bio-medical devices at room temperature.