Domain wall pinning through nanoscale interfacial Dzyaloshinskii–Moriya interaction

Neuromorphic computing (NC) has been gaining attention as a potential candidate for artificial intelligence. The building blocks NC are neurons and synapses. Research studies have indicated that domain wall (DW) devices one of the most energy-efficient contenders realizing NC. Moreover, synaptic functions can be achieved by obtaining multi-resistance states in DW devices. However, with no pinning, it is difficult to control position, hence achieving multilevel resistance difficult. Here, we proposed concept nanoscale interfacial Dzyaloshinskii–Moriya interaction (iDMI) controllably stopping DWs at specific positions, hence, states. We show iDMI forms an energy barrier (well), which pin pinning sites. tunable depinning current density was changing width constant confinement region. also studied device five successive This feature proof-of-concept concept. Based on these observations, magnetic tunnel junction—where free layer made up concept—can fabricated achieve synapses applications.