Leenders, R. A. and Kovalenko, O. Y. and Saito, Y. and Vovk, N. R. and Kimel, A. V. and Mikhaylovskiy, R. V. (2025) THz-Driven Spin Dynamics in Orthoferrites with Kramers and Non-Kramers Rare-Earth Ions. Physical review letters, 135 (24): 246703. ISSN 0031-9007
Full text not available from this repository.Abstract
We study the THz-driven spin dynamics of the canted antiferromagnet ErFeO 3 across the spin reorientation temperatures 80–90 K. The amplitudes of the soft antiferromagnetic resonance mode are drastically enhanced by an order of magnitude in the middle of the spin reorientation temperature interval in ErFeO 3 . Conversely, in the phenomenologically similar magnetic system of TmFeO 3 , exhibiting the same phase transitions at very similar temperatures, this enhancement is not observed. We attribute this enhancement in ErFeO 3 to the dynamic interaction of the iron 3 d spins with the rare-earth 4 f -electronic transitions of the Kramers Er 3 + ions. We confirm this interpretation by comparing measurements on TmFeO 3 , where the non-Kramers Tm 3 + electronic states do not strongly couple to the antiferromagnetic mode. Thus, our results indicate that the character of the microscopic electronic 4 f states may drastically alter the ultrafast magnetic response in the materials with otherwise very similar static magnetic properties and phase diagrams.