摘要
与外加磁场和热辅助磁反转相比,全光磁反转将磁化反转时间缩短至100 ps之内,得到了人们的广泛关注。其中,亚铁磁材料GdFeCo是能够实现单脉冲全光磁反转的重要材料,在全光磁存储领域中具有巨大的潜在应用价值。本文利用微观三温度模型(M3TM)理论模拟并实验验证了GdFeCo材料因热效应所引起的全光磁反转过程。具体研究了GdFeCo材料在单脉冲激发下磁化场的全光磁动力学过程,以及GdFeCo材料的全光磁响应末状态随激光脉冲能量与脉宽的变化关系。与原子自旋模型和Landau-Lifshitz-Bloch(LLB)模型相比,M3TM更简洁地给出了单脉冲激发下GdFeCo材料磁化场随时间的变化关系以及角动量转移的量子化关系,为基于热效应的全光磁反转的快速、大面积计算提供了有效手段。
Compared with magnetic switching by an external magnetic field or by a heat-assisted manner,all-optical switching(AOS)can complete the switching process within 100 ps,which has attracted extensive attention from researchers.Among the magneto-optical materials which can realize AOS,the ferrimagnetic GdFeCo has the ability to realize single-shot AOS and possesses great potential in all-optical magnetic storage.In this paper,a microscopic three-temperature model(M3TM)is utilized to simulate the AOS process of GdFeCo,which is also demonstrated experimentally,under the excitation of a single laser pulse based on the heating effect.By using this M3TM,the AOS dynamics and the final magnetization states of GdFeCo induced by single laser pulses with different energy and pulse widths are calculated and analyzed concretely.Compared with the atomic spin model and the Landau-Lifshitz-Bloch(LLB)model,M3TM provides a more concise time-varying expression of the magnetization of GdFeCo and explicitly addresses the dissipation of angular momentum after the laser-pulse excitation,which enables faster calculations of the heat-induced magnetization dynamics in magneto-optical materials with large areas.
作者
姚涵
王思聪
魏琛
曹耀宇
李向平
Yao Han;Wang Sicong;Wei Chen;Cao Yaoyu;Li Xiangping(Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications,Institute of Photonics Technology,Jinan University,Guangzhou,Guangdong 510632,China)
出处
《光电工程》
CAS
CSCD
北大核心
2019年第3期122-130,共9页
Opto-Electronic Engineering
基金
国家自然科学基金青年科学基金项目(11604123)
国家自然科学基金优秀青年基金项目(61522504)
国家自然科学基金重点项目(61432007)
中央高校基本科研业务费专项资金资助(21616338)
广东省创新创业团队项目(2016ZT06D081)~~
