  The development of energy-efficient neuromorphic hardware using spintronic
devices based on antiferromagnetic (AFM) skyrmion motion on nanotracks has
gained considerable interest. Owing to its properties such as robustness
against external magnetic fields, negligible stray fields, and zero net
topological charge, AFM skyrmions follow straight trajectories that prevent
their annihilation at nanoscale racetrack edges. This makes the AFM skyrmions a
more favorable candidate over the ferromagnetic (FM) skyrmion for future
spintronic applications. This work proposes an AFM skyrmion-based neuron device
exhibiting the leaky-integrate-fire (LIF) functionality by exploiting thermal
gradient or alternatively perpendicular magnetic anisotropy (PMA) gradient in
the nanotrack for leaky behavior by moving the skyrmion in the direction to
minimize the system energy. Furthermore, it is shown that the AFM skyrmion
couples efficiently to the soft ferromagnetic layer of a magnetic tunnel
junction enabling efficient read-out of the skyrmion. The maximum change of
9.2% in tunnel magnetoresistance (TMR) is estimated for detecting the AFM
skyrmion. Moreover, the proposed neuron device has the energy dissipation of
4.32 fJ per LIF operation thus, paving the path for developing energy-efficient
devices in antiferromagnetic spintronics for neuromorphic computing.
