  A magnetic skyrmionium can be perceived as an association of two magnetic
skyrmions with opposite topological charges. In this work, we have investigated
the transformation of skyrmionium into multi-skyrmionic states via domain wall
(DW) pairs in three different devices with variable geometric configurations.
The same device geometries were considered for single ferromagnetic layer as
well as synthetic antiferromagnetic (SAF) system. It is observed that by tuning
the current density, deterministic generation of skyrmions is possible via the
spin transfer torque (STT). The proposed device is efficiently adjustable to
change the number of skyrmions . The results may lead to development of
skyrmion-based devices for neuromorphic and unconventional computing.
