文章信息/Info

Title:

Surface Acoustic Wave Assisted Magnetic Domain Wall Motion in Ferrimagnetic CoTb Alloy

文章編號:

1674-3962(2021)10-0737-06

作者:

鄭文慧1; 2; 邊肖南1; 藺濤1; 曹洋3;  蘇丹1; 孫一銘1; 楊德政3; 閻照文2; 雷娜1

（1. 北京航空航天大學集成電路科學與工程學院，北京 100191）（2. 北京航空航天大學電子信息工程學院，北京 100191）（3. 蘭州大學 磁學與磁性材料教育部重點實驗室，蘭州 730000）

Author(s):

ZHENG Wenhui1; 2;  BIAN Xiaonan1;  LIN Tao1;  CAO Yang3;  SU Dan1;  SUN Yiming1;  YANG Dezheng3;  YAN Zhaowen2;  LEI Na1

(1.School of Integrated Circuit Science & Engineering, Beihang University, Beijing 100191, China) (2.School of Electronic and Information Engineering, Beihang University, Beijing 100191, China) (3.Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000, China）

關鍵詞:

聲表面波; 亞鐵磁; CoTb薄膜; 矯頑場; 磁疇壁移動

Keywords:

surface acoustic wave (SAW);  ferrimagnetism;  CoTb film;  coercive field;  domain wall motion

分類號:

O482.52+4

DOI:

10.7502/j.issn.1674-3962.202107016

文獻標志碼:

A

摘要:

利用電壓產生的動態應力——聲表面波調控材料磁性，具有高效率、低功耗和長傳輸距離等優點，近年來成為自旋電子學領域研究的熱點。亞鐵磁材料因其較快的磁疇壁移動速率而深受關注，因此，探究聲表面波輔助作用下亞鐵磁體系中磁疇壁的移動，對磁存儲、磁邏輯等自旋電子器件的研究具有重要意義。以具有垂直磁各向異性的亞鐵磁CoTb薄膜作為研究材料體系，制備出聲表面波與亞鐵磁材料的耦合器件，研究了聲表面波對CoTb薄膜矯頑場以及磁疇壁移動的調控效應。實驗表明，在聲表面波的輔助作用下CoTb薄膜的矯頑場減小了10%。經分析確認，磁疇成核場及磁疇壁傳播場的減弱是矯頑場減小的主要原因。此外，利用磁光克爾顯微鏡觀測磁疇壁移動，發現在聲表面波的輔助下磁疇壁移動速率提高了約76%，達到3683 μm/s。在亞鐵磁材料體系中成功實現聲表面波輔助磁疇壁的快速移動，為未來低功耗自旋電子器件發展開辟了新的路徑。

Abstract:

Voltage induced surface acoustic wave (SAW) is a hot research topic for manipulating magnetic properties in spintronics, due to its characteristics of high efficiency, low power consumption and long propagation distance. The ferrimagnet has attracted much attentions due to its fast magnetic domain wall (DW) motion. The study of its DW motion assisted by SAW is of great significance for the magnetic memory and DW logic devices. Here, we chose ferrimagnetic CoTb film with perpendicular magnetic anisotropy, and fabricated the coupled device of the SAW and Hall bar structure. The coercive fields and DW motion in CoTb film under SAW are explored by magneto-optical Kerr microscopy. We found the coercive fields reduced by 10% in CoTb film system, which is mainly originated from the reduction of the nucleation and propagation fields under the SAW. Furthermore, we observed the DW motion speed increased up to 76% with the assistance of the SAW, which reached 3683 μm/s. Our work has successfully realized the rapid DW motion driven by SAW in the ferrimagnetic system, which provides an alternative to the future low-consumption spintronic devices.