Unconventional Spin Pumping and Magnetic Damping in an Insulating Compensated Ferrimagnet

• Main Authors: Chen, A. (Author), Fang, B. (Author), Li, Y. (Author), Liu, C. (Author), Liu, H. (Author), Ma, Y. (Author), Manchon, A. (Author), Shen, K. (Author), Zhang, C. (Author), Zhang, X. (Author), Zheng, D. (Author)
• Format: Article
• Language: English
• Published: John Wiley and Sons Inc 2022
• Subjects: Antiferromagnetic systems; Coherent and incoherent spin current; coherent and incoherent spin currents; Damping; Ferrimagnetics; Ferrimagnetism; Ferrimagnets; Ferromagnetic materials; Ferromagnetism; Fundamental physics; Gadolinium compounds; handedness; Handedness; Insulating compensated ferrimagnet; insulating compensated ferrimagnets; Insulation; Iron compounds; magnetic damping; Magnetic damping; Pumps; Spin currents; spin pumping; Spin waves; Spin-pumping
• Online Access: View Fulltext in Publisher
• ISBN: 09359648 (ISSN)
• DOI: 10.1002/adma.202200019

Recently, the interest in spin pumping (SP) has escalated from ferromagnets into antiferromagnetic systems, potentially enabling fundamental physics and magnonic applications. Compensated ferrimagnets are considered alternative platforms for bridging ferro- and antiferromagnets, but their SP and the associated magnetic damping have been largely overlooked so far despite their seminal importance for magnonics. Herein, an unconventional SP together with magnetic damping in an insulating compensated ferrimagnet Gd3Fe5O12 (GdIG) is reported. Remarkably, the divergence of the nonlocal effective magnetic damping induced by SP close to the compensation temperature in GdIG/Cu/Pt heterostructures is identified unambiguously. Furthermore, the coherent and incoherent spin currents, generated by SP and the spin Seebeck effect, respectively, undergo a distinct direction change with the variation of temperature. The physical mechanisms underlying these observations are self-consistently clarified by the ferrimagnetic counterpart of SP and the handedness-related spin-wave spectra. The findings broaden the conventional paradigm of the ferromagnetic SP model and open new opportunities for exploring the ferrimagnetic magnonic devices. © 2022 The Authors. Advanced Materials published by Wiley-VCH GmbH.