Multi-state stripe domain racetrack memory devices utilizing Weyl magnetoresistance

Magnetoresistive effects, such as the tunneling magnetoresistance seen in Magnetic Tunnel Junctions (MTJs), are foundational to the development of spintronic nanodevices. Despite the reliable and efficient write performance, along with great promise for MTJ-based spintronic devices, the readout in CoFeB/MgO/CoFeB MTJs is bounded by the room temperature spin-polarization of CoFe and defects in the MTJ heterostructure. Recently, groups have predicted a massive (>10⁵%) magnetoresistance across magnetic Weyl Semimetal (MWSM) domain walls or in MWSM MTJs. In this work, we instantiate the Dirac equation on a lattice and model NEGF transport through magnetic stripe domains in a toy MWSM Hamiltonian. We show that the device conductance is strongly modulated by the number of domain walls in the active region of the device, providing a means to encode multiple resistance states in a single racetrack device. Additionally, we consider the effects of these periodic magnetic patterns on the electronic structure of the MWSM lattice and show tunable flat bands in the direction of transport. This work elucidates both the physical behavior and computing applications of domain wall-MWSM devices.