Research Projects

This project aims to stabilize magnetic skyrmions in synthetic antiferromagnetic (SyAF) multilayers for spintronics applications. The team aims to control the interfacial Dzyaloshinskii-Moriya interaction, stabilize skyrmions and chiral-domain walls in heavy metal/ferromagnetic (HM/FM) multilayers, stabilize skyrmion bubbles in HM/FM multilayers, and propel these skyrmion bubbles at the highest velocity, 260 m/s for 3 x 1011 A/m2 current density by spin-orbit torques. Despite extensive work on FM-based skyrmion devices, their technological relevance is declining due to finite dipole fields, topological damping, and finite Magnus forces. The SyAF-based skyrmions hold potential for various spintronics applications due to their vanishing dipole fields, suppression of topological damping, and absence of Magnus force. To realize the full potential of SyAF-based skyrmions, the team will explore material combinations to prepare SyAF by growing successive FM-layers separated by nonmagnetic metals, such as CoFeB, and combining heavy metals and nonmagnetic oxide materials to establish strong Fert-Levy type (Rashba-type) iDMI at the interfaces between the heavy metal and FM layers. Magnetic measurements will be performed to ascertain the SyAF ground state and perpendicular magnetocrystalline anisotropy (PMA), and the team will use Kerr microscopy to propel SyAF-skyrmions with zero skyrmion Hall-angle and high velocities. Magnetoresistance measurements will be performed to detect the SyAF-skyrmions, and a memory device will be fabricated to encode information. This project will lift the limitations faced by FM-based skyrmions and advance spintronics on SyAF-skyrmions for technological applications.

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