2025/09/13 by Omolara A. Bakare, Galen T. Street, Bakare, Omolara A. +9
Materials Science · Physics and Astronomy · #Atomic and Subatomic Physics Research #FOS: Physical sciences #Magnetic Properties of Alloys #Magnetic properties of thin films #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
paper · pdf · doi:10.48550/arxiv.2509.11005
openalex publication_date 2025/09/13 · openalex created_date 2025/10/12 · openalex updated_date 2026/07/28
Excited ferromagnets can pump spin angular momentum, along with possibly orbital angular momentum. Among elemental ferromagnets, Ni has been proposed to exhibit substantial orbital pumping relative to spin pumping. Here, we search for a signature of orbital pumping by Ni, specifically by comparing out-of-plane ferromagnetic resonance in heterostructures without Ni (FeV/Nb) and with Ni (FeV-Ni/Nb). The FeV/Nb series shows a clear increase in Gilbert damping with the Nb sink thickness, attributed to spin pumping from FeV to Nb. Surprisingly, the FeV-Ni/Nb series exhibits no such damping increase, revealing no significant spin or orbital pumping from Ni to Nb. Our results offer a fresh perspective on angular-momentum transfer in Ni-based heterostructures, suggesting that the interpretation of some strong orbitronic effects may require further consideration.