Multiple magneto-functional properties of Ni46Mn41In13 shape memory alloy

• Metastability and field-induced arrested state.
• Giant negative magnetoresistance.
• Large inverse magnetocaloric effect.
• Large exchange bias despite extremely small coercive field.
• Incipient antiferromagnetism.

The transport and magnetic properties of ferromagnetic shape memory alloy of nominal composition Ni46Mn41In13 are reported. The alloy undergoes martensitic phase transition (MPT) around 240 K. The region around this structural transition is found to be highly metastable and susceptible to the applied magnetic field. Giant negative magnetoresistance (∼ −64% at 70 kOe) is observed in the vicinity of the thermally driven MPT. The existence of large inverse magnetocaloric effect around the MPT is also confirmed by the direct measurement using modulated ac field technique. The sample shows large exchange bias at low temperature. The role of Mn–Mn intersite antiferromagnetic correlation is discussed for the above magneto-functional behaviors.