Experimental observation of magnetic bobbers for a new concept of magnetic solid-state memory

TL;DR

This paper reports the experimental observation of chiral bobbers, a new magnetic state, coexisting with skyrmions, suggesting a novel data encoding method for magnetic memory that does not require maintaining fixed distances between bits.

Contribution

It provides the first direct observation of chiral bobbers and proposes a new magnetic memory concept using skyrmions and bobbers for data encoding.

Findings

Chiral bobbers coexist with skyrmions in magnetic materials.

A new data encoding approach using skyrmions and bobbers is proposed.

This method eliminates the need for fixed distances between data bits.

Abstract

The use of chiral skyrmions, which are nanoscale vortex-like spin textures, as movable data bit carriers forms the basis of a recently proposed concept for magnetic solid-state memory. In this concept, skyrmions are considered to be unique localized spin textures, which are used to encode data through the quantization of different distances between identical skyrmions on a guiding nanostripe. However, the conservation of distances between highly mobile and interacting skyrmions is difficult to implement in practice. Here, we report the direct observation of another type of theoretically-predicted localized magnetic state, which is referred to as a chiral bobber (ChB), using quantitative off-axis electron holography. We show that ChBs can coexist together with skyrmions. Our results suggest a novel approach for data encoding, whereby a stream of binary data representing a sequence of ones and zeros can be encoded via a sequence of skyrmions and bobbers. The need to maintain defined distances between data bit carriers is then not required. The proposed concept of data encoding promises to expedite the realization of a new generation of magnetic solid-state memory.