| Autor: |
Shelukhin, L. A., Kuzikova, A. V., Telegin, A. V., Bessonov, V. D., Ognev, A. V., Samardak, A. S., Park, Junho, Kim, Young Keun, Kalashnikova, A. M. |
| Rok vydání: |
2024 |
| Předmět: |
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| Druh dokumentu: |
Working Paper |
| Popis: |
The development of spintronic emitters of broadband THz pulses relies on designing heterostructures where processes of laser-driven spin current generation and subsequent spin-to-charge current conversion are the most efficient. An interface between ferromagnetic and nonmagnetic layers in the emitter is one of the critical elements. Here, we study experimentally single-cycle THz pulse generation from a laser-pulse excited Pt/Co emitter with a composition gradient interface between Pt and Co and compare it with the emission from a conventional Pt/Co structure with an abrupt interface. We find that the gradient interface enhances the efficiency of optics-to-THz conversion by a factor of two in a wide range of optical fluences up to 3 mJ cm$^{-2}$. We reveal that this enhancement is caused by a pronounced increase in transmittance of the laser-driven spin-polarized current through the gradient interface compared to the abrupt one. Furthermore, we find that such a transmission deteriorates with laser fluence due to the spin accumulation effect. |
| Databáze: |
arXiv |
| Externí odkaz: |
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