| Autor: |
Rongione, E., Gueckstock, O., Mattern, M., Gomonay, O., Meer, H., Schmitt, C., Ramos, R., Saitoh, E., Sinova, J., Jaffrès, H., Mičica, M., Mangeney, J., Goennenwein, S. T. B., Geprägs, S., Kampfrath, T., Kläui, M., Bargheer, M., Seifert, T. S., Dhillon, S., Lebrun, R. |
| Rok vydání: |
2022 |
| Předmět: |
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| Druh dokumentu: |
Working Paper |
| Popis: |
Antiferromagnetic materials have been proposed as new types of narrowband THz spintronic devices owing to their ultrafast spin dynamics. Manipulating coherently their spin dynamics, however, remains a key challenge that is envisioned to be accomplished by spin-orbit torques or direct optical excitations. Here, we demonstrate the combined generation of broadband THz (incoherent) magnons and narrowband (coherent) magnons at 1 THz in low damping thin films of NiO/Pt. We evidence, experimentally and through modelling, two excitation processes of magnetization dynamics in NiO, an off-resonant instantaneous optical spin torque and a strain-wave-induced THz torque induced by ultrafast Pt excitation. Both phenomena lead to the emission of a THz signal through the inverse spin Hall effect in the adjacent heavy metal layer. We unravel the characteristic timescales of the two excitation processes found to be < 50 fs and > 300 fs, respectively, and thus open new routes towards the development of fast opto-spintronic devices based on antiferromagnetic materials. |
| Databáze: |
arXiv |
| Externí odkaz: |
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