Large inverse spin Hall effect in BiSb topological insulator for 4 Tb/in2 magnetic recording technology

被引：9

作者：

Huy, Ho Hoang ^{[1
]}

Sasaki, Julian ^{[1
]}

Khang, Nguyen Huynh Duy ^{[1
]}

Namba, Shota ^{[1
]}

Hai, Pham Nam ^{[1
]}

Le, Quang ^{[2
]}

York, Brian ^{[2
]}

Hwang, Cherngye ^{[2
]}

Liu, Xiaoyong ^{[2
]}

Gribelyuk, Michael ^{[2
]}

Xu, Xiaoyu ^{[2
]}

Le, Son ^{[2
]}

Ho, Michael ^{[2
]}

Takano, Hisashi ^{[2
]}

机构：

[1] Tokyo Inst Technol, Dept Elect & Elect Engn, Tokyo 1528552, Japan

[2] Western Digital Inc, San Jose, CA 95119 USA

来源：

APPLIED PHYSICS LETTERS | 2023年 / 122卷 / 05期

基金：

日本科学技术振兴机构;

关键词：

ROOM-TEMPERATURE; MAGNETORESISTANCE; TORQUE;

D O I：

10.1063/5.0135831

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

It is technically challenging to shrink the size of a tunneling magnetoresistance reader to below 20 nm for magnetic recording technology beyond 4 Tb/in(2) due to its complex film stack. Recently, we proposed a reader architecture based on the inverse spin Hall effect to resolve those challenges, referred below as spin-orbit torque (SOT) reader, whose structure consists of a SOT layer and a ferromagnetic layer. However, the heavy metal-based SOT reader has small output voltage and low signal-to-noise ratio (SNR) due to the limited spin Hall angle theta(SH) (< 1) of heavy metals. In this Letter, we demonstrate the integration of BiSb topological insulator with strong inverse spin Hall effect into the SOT reader that can significantly improve the output voltage and SNR. First, we theoretically calculate the noises in a 20 x 20 nm(2) BiSb-based SOT reader to establish the relationships between SNR and theta(SH) at various bias currents. We then demonstrate proof-of-concept BiSb-based SOT readers using CoFe/MgO/BiSb stack, which show large output voltages up to 15 mV at an input current of 9.4 kA/cm(2) at room temperature. We project a giant theta(SH) = 61 for BiSb. Our work demonstrates the potential of BiSb for SOT reader beyond 4 Tb/in(2) magnetic recording technology.

引用

页数：6

共 33 条

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