Tailoring magnetization reversal of a single-domain bar nanomagnet via its end geometry

TL;DR

This paper demonstrates that the magnetization reversal switching field of a single-domain bar nanomagnet can be effectively tuned by modifying its end geometry, offering a new method beyond aspect ratio adjustments for controlling magnetic properties.

Contribution

It introduces a novel approach to control the switching field of nanomagnets through end geometry tailoring, expanding the design possibilities for magnetic nanodevices.

Findings

Switching field saturates when length exceeds a certain value.

End geometry tailoring allows for highly tunable switching fields.

Method enables control without changing overall size.

Abstract

Nanoscale single-domain bar magnets are building blocks for a variety of fundamental and applied mesoscopic magnetic systems, such as artificial spin ices, magnetic shape-morphing microbots as well as magnetic majority logic gates. The magnetization reversal switching field of the bar nanomagnets is a crucial parameter that determines the physical properties and functionalities of their constituted artificial systems. Previous methods on tuning the magnetization reversal switching field of a bar nanomagnet usually rely on modifying its aspect ratio, such as its length, width and/or thickness. Here, we show that the switching field of a bar nanomagnet saturates when extending its length beyond a certain value, preventing further tailoring of the magnetization reversal via aspect ratios. We showcase highly tunable switching field of a bar nanomagent by tailoring its end geometry without altering its size. This provides an easy method to control the magnetization reversal of a single-domain bar nanomagnet. It would enable new research and/or applications, such as designing artificial spin ices with additional tuning parameters, engineering magnetic microbots with more flexibility as well as developing magnetic quantum-dot cellular automata systems for low power computing.