Publication highlights

Ajaya K. Nayak, Michael Nicklas, Stanislav Chadov, Panchanana Khuntia, Chandra Shekhar, Adel Kalache, Michael Baenitz, Yurii Skourski, Veerendra K. Guduru, Alessandro Puri, Uli Zeitler, J. M. D. Coey, and Claudia Felser, "Design of compensated ferrimagnetic Heusler alloys for giant tunable exchange bias," Nature Materials 14 (7), 679-684 (2015).
A. K. Nayak, M. Nicklas, S. Chadov, C. Shekhar, Y. Skourski, J. Winterlik, and C. Felser, "Large Zero-Field Cooled Exchange-Bias in Bulk Mn2PtGa," Physical Review Letters 110 (12), 127204-1-127204-5 (2013).

Exchange bias

Exchange bias (EB) corresponds to a shift of the hysteresis loop of a ferromagnet along the magnetic field axis due to interfacial exchange coupling with an adjacent antiferromagnetic layer. It is used for a variety of technological applications, including magnetoresistive read heads and sensors. Though both FM and AFM subsystems are inseparable parts of an EB system, it is the latter that determines the magnitude of the EB in the system. Therefore, it is important to search for an appropriate magnetically compensated material to observe a maximum effect. In this regard, we have designed compensated ferrimagnetic systems Mn3-xPtxGa and Mn2-xFe1+xGa. By optimizing the Mn/Pt ratio in the bulk Mn3-xPtxGa, we observe a giant EB of more than 3 T and a similarly large coercivity in the vicinity of the compensated point. For application prospective we focus to prepare thin films of these samples. We are also looking forward to use these materials as a pinning layer in FM/AFM heterogeneous EB systems [1][2].

<p style="text-align: justify;"><strong>Figure 1:</strong> <em>Design of compensated magnetic state for giant exchange bias.</em></p> Zoom Image

Figure 1: Design of compensated magnetic state for giant exchange bias.

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