The magnetostructural transitions, magnetocaloric effects, and magnetoresistance properties of Ni₄₅Mn₄₃CrSn₁₁ Heusler alloys were investigated using X-ray diffraction (XRD), field-dependent magnetization, and electrical resistivity measurements. A large inverse and direct magnetocaloric effect has been observed in Ni₄₅Mn₄₃CrSn₁₁ across the martensitic and Curie transition temperature, respectively. The values of the latent heat (L = 15.5 J/g) and corresponding magnetic (ΔS_M) and total (∆S_T) entropy changes (ΔS_M = 35 J/kg·K for ΔH = 5T and ∆S_T = 39.7 J/kg·K) have been evaluated using magnetic and differential scanning calorimetry (DSC) measurements, respectively. A substantial jump in resistivity was observed across the martensitic transformation. A large negative magnetoresistance (~67%) was obtained at the magnetostructural transition for a field change of 5 T. The roles of the magnetic and structural changes on the transition temperatures and the potential application of Ni₄₅Mn₄₃CrSn₁₁ Heusler alloys for refrigerator technology are discussed.

Magnetic Heusler alloys X₂BZ (where X and B are 3d elements and Z belongs to the sp group) exhibit diverse magnetic and structural properties, which are important for designing multifunctional smart materials. Electronic band structure calculations demonstrate that, if the valence of element B is higher than that of element X, such alloys (so-called inverse Heusler alloys) can behave differently as compared to traditional Heusler alloys. The growth, the crystal structure, and the magnetic properties of thin films of a new Mn₂FeSi Heusler alloy deposited under various conditions (including various substrates and annealing temperatures) are studied in this work. A temperature-induced structural transition into a low-magnetization martensitic phase and a thermally stable austenitic phase are detected. A magnetic field of 500 Oe applied to some samples at a temperature of 380 K is found to cause a large exchange bias (about 1 kOe) at T = 10 K. The influence of the type of substrate and the annealing temperature on the magnetic and structural properties of the films is discussed.

We investigated the structural, magnetic, magnetocaloric, and magnetotransport properties of Ni₅₀Mn₃₅In₁₅ Heusler alloys via partial substitution of Ni with 3 at.% Bi (Ni₄₇Bi₃Mn₃₅In₁₅) and 3 at.% Si (Ni₄₇Si₃Mn₃₅In₁₅) synthesized by arc melting. X-ray diffraction confirms a predominantly L2₁ cubic structure (space group Fm-3m), while SEM/EDX analysis verifies compositional homogeneity. Temperature-dependent magnetization measurements reveal that the Bi-substituted alloy exhibits a first-order magnetostructural transition associated with the martensitic transformation, followed by a second-order magnetic phase transition from ferromagnetic to paramagnetic behavior near the Curie temperature. In contrast, the Si-substituted alloy shows a single second-order transition with negligible thermal hysteresis, indicating suppression of the martensitic phase. The Curie temperature decreases from 324 K for the parent alloy to 313 K and 286 K for the Bi- and Si-substituted alloys, respectively. A maximum magnetic entropy change of 6.0 Jkg⁻¹K⁻¹ and 4.5 Jkg⁻¹K⁻¹ is observed for the Bi- and Si-substituted alloys, respectively, under an applied magnetic field change of 50 kOe, with corresponding relative cooling power values of 303 Jkg⁻¹ and 345 Jkg⁻¹. These results demonstrate that lattice expansion (Bi) and contraction (Si) distinctly modify Mn–Mn exchange interactions, enabling tunable magnetocaloric performance in Ni–Mn–In Heusler alloys.

We investigated the structural, magnetic, magnetocaloric, and magnetotransport properties of Ni₅₀Mn₃₅In₁₅ Heusler alloys by partial substitution of Ni with 3 at.% Bi (Ni₄₇Bi₃Mn₃₅In₁₅) and Si (Ni₄₇Si₃Mn₃₅In₁₅) synthesized by arc-melting. X-ray diffraction confirms a predominant L₂₁ cubic structure (space group Fm-3m), while SEM/EDX verifies compositional homogeneity. Temperature-dependent magnetization measurements reveal that the Bi-substituted alloy exhibits a first-order magnetostructural transition associated with the martensitic transformation, followed by a second-order ferromagnetic–paramagnetic transition near the Curie temperature. In contrast, the Si-substituted alloy shows a single second-order transition with negligible thermal hysteresis, indicating suppression of the martensitic phase. The Curie temperature decreases from 324 K for the parent alloy to 313 K and 286 K for the Bi- and Si-substituted alloys, respectively. A maximum magnetic entropy change of 6.0 Jkg^-1K^-1 and 4.5 Jkg^-1K^-1 is obtained under an applied magnetic field change of 50 kOe for the Bi- and Si-substituted alloys, respectively, with corresponding relative cooling power values of 303 Jkg^-1 and 345 Jkg^-1. These results demonstrate that lattice expansion (Bi) and contraction (Si) distinctly modify Mn–Mn exchange interactions, enabling tunable magnetocaloric performance in Ni–Mn–In Heusler alloys.