Seminar: Magnetism at the interfaces and in nanostructures for future spintronic applications

Ferromagnetic thin films have been investigated for last few decades for the advancement of fundamental research and data storage technology. Hence, it is necessary to understand the magnetic properties like domain structure and magnetization reversal of these magnetic thin films. In this context, the role of interactions and interfaces becomes very important to explore and tune novel magnetic properties for future spintronic applications. The magnetization reversal can be studied simultaneously with domain imaging using the state-of-art magneto-optic Kerr effect (MOKE) microscopy and magnetic force microscopy. I will discuss the role of architecture such as dot and antidot arrays for domain engineering. In magnetic dot arrays or strongly interacting magnetic nanoparticles, the dipolar interaction leads to superferromagnetic domain state [1-3]. Further, the statics and dynamics of DW can be modified via interfacial Dzyaloshinskii-Moriya interaction (iDMI) which is significant in an inversion asymmetric system [4-6]. Further, we will discuss how magnetic interface (spinterface) can be engineered at the interface between magnetic and non-magnetic (organic) thin films. In this regard, I will review our recent results on creating magnetic fullerene in ferromagnetic/C60 bilayers [7-14]. It has been found that the magnetic fullerene can exhibit magnetic moment of ~ 3 µB per cage. Next, we will discuss how the inter-layer interactions can lead to layer-by-layer magnetization reversal in ferromagnetic/non-magnetic multilayers [18]. Further, topological magnetic structures such as skyrmions can be modified via interfacial Dzyaloshinskii-Moriya interaction (iDMI) which is significant in an inversion asymmetric system. In this context, I will discuss our recent work on driving skyrmions with low threshold current density [15-20].

Acknowledgement: I like to thank my past and present group members and collaborators for their continuous collaboration and support to carry out this work. We like to thank the department of atomic energy (DAE), DST-Nanomission, DST-SERB, Govt. of India and DST-DAAD, DST-Poland, Newton funds etc. for financial support to carry out these works.

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