Novel magnetic domain wall motion scheme in ultra-narrow planar wire and its evolution to three-dimensional device

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H05521
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Electron device/Electronic equipment
• Research Institution: Tohoku University
• Principal Investigator: Fukami Shunsuke 東北大学, 電気通信研究所, 准教授 (60704492)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 電流誘起磁壁移動 / スピントルク / 微細化 / 3次元デバイス

Outline of Final Research Achievements

This research aimed at realizing current-induced magnetic domain wall motion in ultra-narrow nanowires and three-dimensional pillar-shaped devices. First, the physical limit of miniaturization for the case of perpendicular-easy-axis wire was experimentally clarified to be around 20 nm and the underlying physics was revealed by micromagnetic simulation. Then, the research was shifted to the in-plane-easy-axis magnetic wire and a domain wall motion was demonstrated in wire with the width of 13 nm by applying a new concept. Finally, the pillar devices with the diameter of less than 10 nm and the thickness of 15 nm were fabricated and magnetization switching was experimentally investigated. The experimental results were well described by analytical model, and numerical simulation suggests the possibility of three-dimensional device when one design the thickness to be more than 30 nm. A large portion of the original objectives of this research were achieved.

Free Research Field

スピントロニクス

Academic Significance and Societal Importance of the Research Achievements

スピントロニクスの原理を利用することで超低消費電力な集積回路を実現できる。電流誘起磁壁移動はスピントロニクス関連現象の一つであり、超低消費電力集積回路を実現するスピントロニクス素子の動作原理として利用できる。応用上はスピントロニクス素子の性能を維持しながら、あるいは向上させながら素子のサイズを微細化できることが望ましい。本研究は、10 nm程度の究極の微細世代においても優れた特性を実現できる電流誘起磁壁移動を利用したスピントロニクス素子の設計指針を実験で明らかにし、かつ現在の２次元的なデバイス構造から飛躍し、３次元的な構造の実現への見通しをつけたものである。