Tapas Samanta

Effects of hydrostatic pressure on magnetostructural transitions and magnetocaloric properties in (MnNiSi)1−x(FeCoGe)x

This work was supported by the European Regional Development Fund (ERDF) through the Ireland Wales Programme (INTERREG 4A). DR acknowledges the support of the Russian Foundation for basic Research through grant 10-01-93112.

Phase transitions and magnetocaloric and transport properties in off-stoichiometric GdNi2Mnx

The structural, magnetic, magnetocaloric, transport, and magnetoresistance properties of the rare-earth intermetallic compounds GdNi2Mnx (0.5u2009≤u2009xu2009≤u20091.5) have been studied. The compounds with xu2009=u20090.5 and 0.6 crystallize in the cubic MgCu2 type phase, whereas samples with xu2009≥u20090.8 form a mixed MgCu2 and rhombohedral PuNi3 phase. A second order magnetic phase transition from a ferromagnetic to paramagnetic state was observed near the Curie temperature (TC). The GdNi2Mnx (0.5u2009≤u2009xu2009≤u20091.5) compounds order in a ferrimagnetic structure in the ground state. The largest observed values of magnetic entropy changes (at TC for ΔHu2009=u20095T) were 3.9, 3.5, and 3.1u2009J/kg K for xu2009=u20090.5, 0.6, and 0.8, respectively. The respective relative values of the cooling power were 395, 483, and 220u2009J/kg. These values are greater than some well-known prototype magnetocaloric materials such as Gd (400u2009J/kg) and Gd5Si2Ge2 (240u2009J/kg). Analysis of the resistivity data showed a T2 dependence at low temperatures, suggesting strong electron-phonon...

The effects of substituting Ag for In on the magnetoresistance and magnetocaloric properties of Ni-Mn-In Heusler alloys

The effect of substituting Ag for In on the structural, magnetocaloric, and thermomagnetic properties of Ni50Mn35In15−xAgx (x = 0.1, 0.2, 0.5, and 1) Heusler alloys was studied. The magnitude of the magnetization change at the martensitic transition temperature (TM) decreased with increasing Ag concentration. Smaller magnetic entropy changes (ΔSM) were observed for the alloys with larger Ag concentrations and the martensitic transition shifted to higher temperature. A shift of TM by about 25 K to higher temperature was observed for an applied hydrostatic pressure of P = 6.6 kbar with respect to ambient pressure. A large drop in resistivity was observed for large Ag concentration. The magnetoresistance was dramatically suppressed due to an increase in the disorder of the system with increasing Ag concentration. Possible mechanisms responsible for the observed behavior are discussed.

Complex superconductivity in the noncentrosymmetric compound Re6Zr

We report the electronic structure, synthesis, and measurements of the magnetic, transport, and thermal properties of the polycrystalline noncentrosymmetric compound Re

Magnetic and magnetocaloric properties of Dy5Pd2: Role of magnetic irreversibility

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Phase diagram and magnetocaloric effects in Ni1-xCrxMnGe1.05

Zr. We observed a bulk superconducting transition at temperature

Barocaloric and magnetocaloric effects in (MnNiSi)1−x(FeCoGe)x

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Hydrostatic pressure-induced modifications of structural transitions lead to large enhancements of magnetocaloric effects in MnNiSi-based systems

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Multifunctional properties related to magnetostructural transitions in ternary and quaternary Heusler alloys

6.7 K, and measured the resistivity, heat capacity, thermal conductivity, and the London penetration depth below the transition, as well as performed doping and pressure studies. From these measurements we extracted the critical field, and the superconducting parameters of Re