Lim, YoungminNepal, BhuwanSmith, David A.Wu, ShuangSrivastava, AbhishekNakarmi, PrabandhaMewes, ClaudiaJiang, ZijianGupta, AdbhutViehland, Dwight D.Klewe, ChristophShafer, PadraicPark, In JunMabe, TimothyAmin, Vivek P.Heremans, Jean J.Mewes, TimEmori, Satoru2025-05-022025-05-022023-10Lim, Y., Nepal, B., Smith, D. A., Wu, S., Srivastava, A., Nakarmi, P., Mewes, C., Jiang, Z., Gupta, A., Viehland, D. D., Klewe, C., Shafer, P., Park, I. J., Mabe, T., Amin, V. P., Heremans, J. J., Mewes, T., & Emori, S. (2023). Suppression of spin pumping at metal interfaces. APL Materials, 11(10), 101121. https://doi.org/10.1063/5.0156429https://hdl.handle.net/1805/47671An electrically conductive metal typically transmits or absorbs a spin current. Here, we report on evidence that interfacing two metal thin films can suppress spin transmission and absorption. We examine spin pumping in spin-source/spacer/spin-sink heterostructures, where the spacer consists of metallic Cu and Cr thin films. The Cu/Cr spacer largely suppresses spin pumping—i.e., neither transmitting nor absorbing a significant amount of spin current—even though Cu or Cr alone transmits a sizable spin current. The antiferromagnetism of Cr is not essential for the suppression of spin pumping, as we observe similar suppression with Cu/V spacers with V as a nonmagnetic analog of Cr. We speculate that diverse combinations of spin-transparent metals may form interfaces that suppress spin pumping, although the underlying mechanism remains unclear. Our work may stimulate a new perspective on spin transport in metallic multilayers.enAttribution 4.0 Internationalmagnetization dynamicsspin pumpingheterostructuresArticle