Computing with spins and magnets

TL;DR

This paper reviews the potential of spin and magnetic devices, like magnetic tunnel junctions, for nonvolatile memory and reconfigurable logic, highlighting their advantages over traditional transistor-based systems.

Contribution

It provides a comprehensive overview of spin-based logic devices, their characteristics, and the challenges in materials, integration, and fabrication from mesoscopic to atomic scales.

Findings

Magnetic tunnel junctions enable resistance changes based on magnetization.

Spin-based devices can function as logic gates with nonvolatile and reconfigurable properties.

Challenges include materials compatibility and fabrication at atomic scales.

Abstract

The possible use of spin and magnets in place of charge and capacitors to store and process information is well known. Magnetic tunnel junctions are being widely investigated and developed for magnetic random access memories. These are two terminal devices that change their resistance based on switchable magnetization of magnetic materials. They utilize the interaction between electron spin and magnets to read information from the magnets and write onto them. Such advances in memory devices could also translate into a new class of logic devices that offer the advantage of nonvolatile and reconfigurable information processing over transistors. Logic devices having a transistor-like gain and directionality could be used to build integrated circuits without the need for transistor-based amplifiers and clocks at every stage. We review device characteristics and basic logic gates that compute with spins and magnets from the mesoscopic to the atomic scale, as well as materials, integration, and fabrication challenges and methods.