收稿日期: 2021-04-09
网络出版日期: 2022-03-28
Study of polarized laser-induced ultrafast spin dynamics on [Pt/Co]3MnIr film
Received date: 2021-04-09
Online published: 2022-03-28
使用时间分辨的磁光克尔泵浦探测系统, 研究了铁磁-反铁磁(Ferromagnetism-Antiferromagnetism, FM-AFM)薄膜在不同偏振态的泵浦光激发下退磁信号的区别, 以及光子角动量和激光热效应在泵浦探测过程中发挥的作用. 基于逆法拉第效应, 圆偏振光能够生成有效感应磁场, 诱导电子轨道自旋定向. 受光子携带角动量方向的影响, 瞬态克尔峰的方向会发生改变, 其方向与外磁场方向无关. 通过改变MnIr层厚度的实验发现, 顺磁电子的磁化是瞬态克尔峰的主要来源. 这对未来进一步探索全光磁翻转中的自旋动力学机制具有重要意义.
关键词: [Pt/Co]3MnIr 薄膜; 偏振光诱导超快自旋动力学; 角动量
郑文奇 , 刘雨 , 胡海林 , 楼柿涛 . 偏振光诱导的[Pt/Co]3MnIr薄膜中的电子自旋动力学研究[J]. 华东师范大学学报(自然科学版), 2022 , 2022(2) : 120 -126 . DOI: 10.3969/j.issn.1000-5641.2022.02.014
In this study, ultrafast spin dynamics on FM-AFM (ferromagnetism-antiferromagnetism) thin film were explored using pump-probe technology with circularly polarized and linear pump beams. Circularly polarized light generates an effective inducting magnetic field, which is called the inverse Faraday effect. The direction of the transient Kerr peak only depends on the angular momentum of photons. The amplitude of the Kerr peak depends on the thickness of the MnIr film. This may be attributed to the fact that the transient Kerr peak originates from the magnetization of paramagnetic electrons. This study may help further the understanding of spin dynamics in HD-AOS (Helicity-Dependent All Optical Switching).
1 | SANDER D, VALENZUELA S O, MAKAROV D, et al. The 2017 Magnetism Roadmap. Journal of Physics D: Applied Physics, 2017, 50 (36): 363001. |
2 | MANGIN S, GOTTWALD M, LAMBERT C-H, et al. Engineered materials for all-optical helicity-dependent magnetic switching. Nature Materials, 2014, 13 (3): 286- 292. |
3 | LAMBERT C-H, MANGIN S, VARAPRASAD B S D C S, et al. All-optical control of ferromagnetic thin films and nanostructures. Science, 2014, 345 (6202): 1337- 1340. |
4 | KIRILYUK A, KIMEL A V, RASING T. Ultrafast optical manipulation of magnetic order. Reviews of Modern Physics, 2010, 82 (3): 2731- 2784. |
5 | STANCIU C D, HANSTEEN F, KIMEL A V, et al. All-Optical Magnetic Recording with Circularly Polarized Light. Physical Review Letters, 2007, 99 (4): 047601. |
6 | KIMEL A, KIRILYUK A, USACHEV P A, et al. Ultrafast non-thermal control of magnetization by instantaneous photomagnetic pulses. Nature, 2005, 435 (7042): 655- 657. |
7 | HOHLFELD J, STANCIU CD, REBEI A. Athermal all-optical femtosecond magnetization reversal in GdFeCo. Applied Physics Letters, 2009, 94 (15): 152504. |
8 | DANIEL S, SABINE A, ALEXANDER H, et al. All-optical magnetization recording by tailoring optical excitation parameters. Physical Review B, 2011, 84 (22): 224408. |
9 | El HADRI M S, PIRRO P, LAMBERT C H, et al. Two types of all-optical magnetization switching mechanisms using femtosecond laser pulses. Physical Review B, 2016, 94 (6): 064412. |
10 | El HADRI M S, PIRRO P, LAMBERT C H, et al. Electrical characterization of all-optical helicity-dependent switching in ferromagnetic Hall crosses. Applied Physics Letters, 2016, 108 (9): 092405. |
11 | VALLOBRA P, FACHE T, XU Y, et al. Manipulating exchange bias using all-optical helicity-dependent switching. Physical Review B, 2017, 96 (14): 144403. |
12 | GORCHON J, LAMBERT C H, YANG Y, et al. Single shot ultrafast all optical magnetization switching of ferromagnetic Co/Pt multilayers. Applied Physics Letters, 2017, 111 (4): 042401. |
13 | VAHAPLAR K, KALASHNIKOVA A M, KIMEL A V, et al. All-optical magnetization reversal by circularly polarized laser pulses: Experiment and multiscale modeling. Physical Review B, 2012, 85 (10): 104402. |
14 | GORCHON J, WILSON R B, YANG Y, et al. Role of electron and phonon temperatures in the helicity-independent all-optical switching of GdFeCo. Physical Review B, 2016, 94 (18): 184406. |
15 | ELLIS M O, FULLERTON E E, CHANTRELL R W. All-optical switching in granular ferromagnets caused by magnetic circular dichroism. Scientific Reports, 2016, 6, 30522. |
16 | GRIDNEV V N. Phenomenological theory for coherent magnon generation through impulsive stimulated Raman scattering. Physical Review B, 2008, 77 (9): 094426. |
17 | POPOVA D, BRINGER A, BLüGEL S. Theoretical investigation of the inverse Faraday effect via a stimulated Raman scattering process. Physical Review B, 2012, 85 (9): 094419. |
18 | MENTINK J H, HELLSVIK J, AFANASIEV D V, et al. Ultrafast spin dynamics in multisublattice magnets. Physical Review Letters, 2012, 108 (5): 057202. |
19 | MAAT S, TAKANO K, PARKIN S S, et al. Perpendicular exchange bias of Co/Pt multilayers. Physical Review Letters, 2001, 87 (8): 087202. |
20 | 王向谦. Co基磁性多层膜的磁各向异性和磁化翻转研究 [D]. 兰州: 兰州大学, 2020. |
21 | LI W, YAN J Q, TANG M H, et al. Composition and temperature-dependent magnetization dynamics in ferrimagnetic TbFeCo. Physical Review B, 2018, 97 (18): 184432. |
22 | HU H L, YAN J Q, LI W. Gilbert damping in annealed perpendicular exchange biased CoFeB/Pt/MnIr multilayers. Spin, 2020, 10 (01): 2050008. |
23 | BEAUREPAIRE E, MERLE J C, DAUNOIS A, et al. Ultrafast spin dynamics in ferromagnetic nickel. Physical Review Letters, 1996, 76 (22): 4250- 4253. |
24 | 胡海林. 磁性多层膜的超快退磁动力学研究 [D]. 上海: 华东师范大学, 2020. |
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