Element‐Specific Magnetization Damping in Ferrimagnetic DyCo5 Alloys Revealed by Ultrafast X‐ray Measurements

• DOI: 10.1002/pssr.202100047
• Publication Date: 2021-03-26T20:41:26Z
• Authors: Radu Abrudan; Martin Hennecke; Florin Radu; Torsten Kachel; Karsten Holldack; Rolf Mitzner; Andreas Donges; Sergii Khmelevskyi; András Deák; László Szunyogh; Ulrich Nowak; Stefan Eisebitt; Ilie Radu
• Keywords: Ferrimagnetism; Magnetization dynamics; Magnetic damping; Phenomenological model

The dynamic response of magnetically ordered materials to an ultrashort external stimulus depends on microscopic parameters, such as magnetic moment, exchange, and spin–orbit interactions. Whereas it is well established that, in multicomponent alloys compounds, the speed demagnetization spin switching processes has element‐specific character, magnetization damping was assumed be a universal parameter for all constituent elements irrespective their different couplings electronic structure. Herein, experimental theoretical evidence provided by investigating ultrafast high‐anisotropy ferrimagnetic DyCo 5 alloy femtosecond laser excitation. Strikingly remagnetization dynamics Dy Co moments revealed employing pump–X‐ray circular dichroism probe measurements combined with atomistic (ASD) simulations using ab initio calculated parameters. These observations, fully corroborated ASD simulations, are linked coupling strengths Co, which incorporated phenomenological findings can used recipe tuning magnitude laser‐driven consequently allow control over various functionalities materials.