The understanding of how spins move and can be manipulated at pico- and femtosecond timescales has implications for ultrafast and energy-efficient data-processing and storage applications. However, the possibility of realizing commercial technologies based on ultrafast spin dynamics has been hampered by our limited knowledge of the physics behind processes on this timescale. Recently, it has been suggested that inertial effects should be considered in the full description of the spin dynamics at these ultrafast timescales, but a clear observation of such effects in ferromagnets is still lacking. Here, we report direct experimental evidence of intrinsic inertial spin dynamics in ferromagnetic thin films in the form of a nutation of the magnetization at a frequency of ~0.5 THz. This allows us to reveal that the angular momentum relaxation time in ferromagnets is on the order of 10 ps.
Inertial spin dynamics in ferromagnets / Neeraj, K.; Awari, N.; Kovalev, S.; Polley, D.; Zhou Hagstrom, N.; Arekapudi, S. S. P. K.; Semisalova, A.; Lenz, K.; Green, B.; Deinert, J. -C.; Ilyakov, I.; Chen, M.; Bawatna, M.; Scalera, V.; D'Aquino, M.; Serpico, C.; Hellwig, O.; Wegrowe, J. -E.; Gensch, M.; Bonetti, S.. - In: NATURE PHYSICS. - ISSN 1745-2473. - 17:2(2021), pp. 245-250. [10.1038/s41567-020-01040-y]
Inertial spin dynamics in ferromagnets
Scalera V.;d'Aquino M.;Serpico C.;
2021
Abstract
The understanding of how spins move and can be manipulated at pico- and femtosecond timescales has implications for ultrafast and energy-efficient data-processing and storage applications. However, the possibility of realizing commercial technologies based on ultrafast spin dynamics has been hampered by our limited knowledge of the physics behind processes on this timescale. Recently, it has been suggested that inertial effects should be considered in the full description of the spin dynamics at these ultrafast timescales, but a clear observation of such effects in ferromagnets is still lacking. Here, we report direct experimental evidence of intrinsic inertial spin dynamics in ferromagnetic thin films in the form of a nutation of the magnetization at a frequency of ~0.5 THz. This allows us to reveal that the angular momentum relaxation time in ferromagnets is on the order of 10 ps.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.