Ultrabroadband single-cycle terahertz pulses with peak fields of 300 kV cm−1 from a metallic spintronic emitter
Ultrabroadband single-cycle terahertz pulses with peak fields of 300 kV cm−1 from a metallic spintronic emitter
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DOI：
10.1063/1.4986755
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发表时间：
2017-03
影响因子：
4
通讯作者：
T. Seifert;S. Jaiswal;S. Jaiswal;M. Sajadi;Gerhard Jakob;S. Winnerl;Martin Wolf;Mathias Kläui
中科院分区：
文献类型：
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作者：
T. Seifert;S. Jaiswal;S. Jaiswal;M. Sajadi;Gerhard Jakob;S. Winnerl;Martin Wolf;Mathias Kläui
我们探索了金属自旋电子薄膜堆栈作为强和宽带太赫兹电磁场来源的能力。为此，我们用飞秒激光脉冲(能量5.5mJ，脉宽40fs，波长800 nm)在大面积玻璃衬底(直径7.5 cm)上激发W/CoFeB/Pt三层膜(厚度5.6 nm)。实验测得聚焦后的太赫兹脉冲的脉宽为230ps，峰值电场为300kV cm−1，能量为5nJ。特别是，该波形在其最大幅度的10%处显示出从1到10太赫兹的无间隙频谱，从而有助于在亚皮秒时间尺度上对这一难以到达的频率范围内的物质进行非线性控制。
We explore the capabilities of metallic spintronic thin-film stacks as a source of intense and broadband terahertz electromagnetic fields. For this purpose, we excite a W/CoFeB/Pt trilayer (thickness of 5.6 nm) on a large-area glass substrate (diameter of 7.5 cm) by a femtosecond laser pulse (energy 5.5 mJ, duration 40 fs, and wavelength 800 nm). After focusing, the emitted terahertz pulse is measured to have a duration of 230 fs, a peak field of 300 kV cm−1, and an energy of 5 nJ. In particular, the waveform exhibits a gapless spectrum extending from 1 to 10 THz at 10% of its amplitude maximum, thereby facilitating nonlinear control over matter in this difficult-to-reach frequency range on the sub-picosecond time scale.