Imaging of zero-field target skyrmions in chiral magnetic nanodisks

November 2017

by Fengshan Zheng, Hang Li, Shasha Wang, Dongsheng Song, Chiming Jin, Wenshen Wei, András Kovács, Jiadong Zang, Mingliang Tian, Yuheng Zhang, Haifeng Du, and Rafal E Dunin-Borkowski

A target Skyrmion is a flux-closed spin texture that has twofold degeneracy and is promising as a binary state in next generation universal memories. Although its formation in nanopatterned chiral magnets has been predicted, its observation has remained challenging.

In the present study off-axis electron holography has been used to record images of target Skyrmions in a 160-nm-diameter nanodisk of the chiral magnet FeGe. Experimental measurements are compared with numerical simulations demonstrating switching between two stable degenerate target Skyrmion ground states that have opposite polarities and rotation senses. The observed switching mechanism are discussed.

Further reading:

Fengshan Zheng, Hang Li, Shasha Wang, Dongsheng Song, Chiming Jin, Wenshen Wei, András Kovács, Jiadong Zang, Mingliang Tian, Yuheng Zhang, Haifeng Du, and Rafal E Dunin-Borkowski:
Direct imaging of a zero-field target skyrmion and its polarity switch in a chiral magnetic nanodisk, Physical Review Letters 119 (2017) 197205.

Michael Schirber: Focus: Field-Free Spin Patterns, Physics 10 (2017) 124.