This title appears in the Scientific Report :
2019
Please use the identifier:
http://dx.doi.org/10.1063/1.5099201 in citations.
Please use the identifier: http://hdl.handle.net/2128/22698 in citations.
Magnetically and optically tunable terahertz radiation from Ta/NiFe/Pt spintronic nanolayers generated by femtosecond laser pulses
Magnetically and optically tunable terahertz radiation from Ta/NiFe/Pt spintronic nanolayers generated by femtosecond laser pulses
We generate terahertz (THz) transients by illuminating a few-nanometer-thick Ta/NiFe/Pt nanolayers with a train of linearly polarized 100-fs-wide laser pulses. The transients are ∼1-ps-wide free-space propagating bursts of electromagnetic radiations with amplitudes that are magnetically and opticall...
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Personal Name(s): | Adam, Roman (Corresponding author) |
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Chen, Genyu / Bürgler, Daniel E. / Shou, Tianyu / Komissarov, Ivan / Heidtfeld, Sarah / Hardtdegen, Hilde / Mikulics, Martin / Schneider, Claus M. / Sobolewski, Roman | |
Contributing Institute: |
Elektronische Eigenschaften; PGI-6 Materialwissenschaft u. Werkstofftechnik; ER-C-2 |
Published in: | Applied physics letters, 114 (2019) 21, S. 212405 - |
Imprint: |
Melville, NY
American Inst. of Physics
2019
|
DOI: |
10.1063/1.5099201 |
Document Type: |
Journal Article |
Research Program: |
Controlling Configuration-Based Phenomena Controlling Spin-Based Phenomena |
Link: |
Published on 2019-05-31. Available in OpenAccess from 2020-05-31. Published on 2019-05-31. Available in OpenAccess from 2020-05-31. |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/22698 in citations.
We generate terahertz (THz) transients by illuminating a few-nanometer-thick Ta/NiFe/Pt nanolayers with a train of linearly polarized 100-fs-wide laser pulses. The transients are ∼1-ps-wide free-space propagating bursts of electromagnetic radiations with amplitudes that are magnetically and optically tunable. Their spectral frequency content extends up to 5 THz, and the 3-dB cutoff is at 0.85 THz. The observed transient electromagnetic signals originate from the NiFe/Pt bilayer, and their amplitude dependence on the external magnetic field, applied in the sample plane, very closely follows the static magnetization versus magnetic field dependence of the NiFe film. For the same laser power, excitation with highly energetic, blue light generates THz transients with amplitudes approximately three times larger than the ones resulting from excitation by infrared light. In both cases, the transients exhibit the same spectral characteristics and are linearly polarized in the perpendicular direction to the sample magnetization. The polarization direction can be tuned by rotation of the magnetic field around the laser light propagation axis. The characteristics of our THz spintronic emitter signals confirm that THz transient generation is due to the inverse spin Hall effect in the Pt layer and demonstrate that ferromagnet/metal nanolayers excited by femtosecond laser pulses can serve as efficient sources of magnetically and optically tunable, polarized transient THz radiation. |