铁铂膜厚度对Fe/Pt异质结构太赫兹辐射的影响

黄潘辉; 张晓磊; 楼柿涛

doi:10.3969/j.issn.1000-5641.2017.03.012

铁铂膜厚度对Fe/Pt异质结构太赫兹辐射的影响

doi: 10.3969/j.issn.1000-5641.2017.03.012

华东师范大学精密光谱科学与技术国家重点实验室, 上海 200062

基金项目:

华东师范大学师资队伍建设资金 77102518

详细信息

作者简介:
黄潘辉, 男, 硕士研究生, 研究方向为太赫兹光的产生与探测. E-mail: 423765906@qq.com

通讯作者:
楼柿涛, 男, 硕士生导师, 研究方向为磁性材料的超快现象与扫描探针显微学的研究.E-mail: stlou@admin.ecnu.edu.cn

中图分类号: O441.2
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- 被引次数: 0
出版历程
- 收稿日期: 2016-04-26
- 刊出日期: 2017-05-25

Thickness related THz-TDS of Fe/Pt heterostructure

State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China

摘要

摘要: 本文通过飞秒脉冲激光和铁铂异质结构的相互作用产生太赫兹(Terahertz, THz)脉冲, 并利用时序太赫兹的测量方法, 研究了太赫兹光在金属薄膜中的传播规律.太赫兹光在铁(Fe)膜和铂(Pt)膜中都以指数形式衰减, 但是与金属体材料传播介质及适用于体材料的Drude模型相比, 2~10 nm厚的铁、铂薄膜对太赫兹光的衰减系数明显增加.其原因可能是由于超薄薄膜中电子在膜厚方向的运动受限, 而膜平面内的自由程增加, 导致在膜平面内电场的衰减长度变小.该现象在近红外的飞秒脉冲光中同样存在.
- 太赫兹技术 /
- 异质结构 /
- 时序太赫兹光谱 /
- 铁磁材料
Abstract: This paper investigates the transmission of terahertz pulse in the ultrathin film with terahertz time-domain spectroscopy and the terahertz pulse produced by the interaction between femtosecond laser pulse and Fe/Pt heterostructure. The thickness of the Fe/Pt film ranges from 2 nm to 8 nm. The terahertz wave exponentially decays in Fe and Pt ultrathin films, but it decays much faster in the bulk Fe and Pt. Due to the limitation in the thickness, electrons have much longer free path in the film plane, which increases the conductivity in the film plane. We also find that the laser pulse with 800 nm wavelength also decays faster in the ultrathin film.
- terahertz technology /
- heterostructure /
- terahertz time-domain spectroscopy /
- magnetic material

HTML全文

图 1 时域太赫兹光谱测量装置示意图

Fig. 1 Schematic diagram of THz-TDS

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图 2 (2 nm)Pt层的时序太赫兹光谱

Fig. 2 THz-TDS of 2 nm thickness Pt

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图 3 (a) Fe(2 nm)/Pt(X nm)的时域太赫兹辐射强度; (b)经过FFT的样品频域光谱

Fig. 3 (a) THz-TDS of Fe(2 nm)/Pt(X nm)samples; (b) FFT spectrum of samples

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图 4 0.5 THz成分的幅度随铂厚度衰减曲线

Fig. 4 Siμlation of decay at 0.5 THz with Pt thickness increase

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图 5 (a)Fe(Y nm)/Pt(2 nm)的时域太赫兹光谱; (b)经过FFT的样品频域光谱

Fig. 5 THz-TDS of Fe(Y nm)/Pt(2 nm)samples; (b) FFT spectrum of samples

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图 6 (a)激光随Fe厚度增加的功率衰减情况; (b)考虑激光补偿后的太赫兹幅度衰减情况

Fig. 6 (a)Laser intensity decay with increase of Fe thickness; (b) Compensative decay curveof THz magnitude at 0.5 THz

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