Toward Chirality‐Encoded Domain Wall Logic

Abstract

Nonvolatile logic networks based on spintronic and nanomagnetic technologies have the potential to create high‐speed, ultralow power computational architectures. This article explores the feasibility of “chirality‐encoded domain wall logic,” a nanomagnetic logic architecture where data are encoded by the chiral structures of mobile domain walls in networks of ferromagnetic nanowires and processed by the chiral structures' interactions with geometric features of the networks. High‐resolution magnetic imaging is used to test two critical functionalities: the inversion of domain wall chirality at tailored artificial defect sites (logical NOT gates) and the chirality‐selective output of domain walls from 2‐in‐1‐out nanowire junctions (common operation to AND/NAND/OR/NOR gates). The measurements demonstrate both operations can be performed to a good degree of fidelity even in the presence of complex magnetization dynamics that would normally be expected to destroy chirality‐encoded information. Together, these results represent a strong indication of the feasibility of devices where chiral magnetization textures are used to directly carry, rather than merely delineate, data.

Suppression of Dynamically Induced Stochastic Magnetic Behavior Through Materials Engineering

“…Thus, we conclude the small degree of DFD stochasticity observed in a minority of the Tb-doped devices was likely due to variability in the magnetisation structure of injected DWs, as opposed to inherently stochastic interaction of the DWs with the defect sites. This is an important distinction, as many studies have demonstrated the feasibility of controlling the initial structure/chirality of DWs 6,24,50,51 , while the dynamic interactions of DWs with defect sites is inherently uncontrollable at fields above H WB…”

Magnetic Domain Wall Based Synaptic and Activation Function Generator for Neuromorphic Accelerators

“…19,20 In the absence of any external magnetic field or pinning of the domain wall, the domain wall velocity increases with the current density up to saturation 21 , either expanding or contracting the domain depending on the direction of the applied current. Magnetic domain wall devices have been utilized previously for binary logic 22,23,24,25,26,27 and memory 28,29 applications.…”

An all-electrical magnetic logic gate that harnesses chirality between domains

“…In the past three years, however, there has been a flurry of studies showing reward-related neuronal activity in the cerebellum [6][7][8][9][10][11][12] . What are reward signals doing in an error-correcting part of the brain?…”

“…The DMI both establishes a specific chirality and favours the generation of the correct type of wall -a Néel wall -in Luo and colleagues' set-up. Researchers have previously recognized that chiral domain walls could be used in logic operations 6 , but an all-electrical working logic has been hampered by the lack of a reliable working inverter, the key component for logic operations.…”