Nonlocal Uniform-Mode Ferromagnetic Resonance Spin Pumping

Magnonic transport is an important component in realizing THz antiferromagnetic spintronic devices.  Due to the fundamental similarities between ferrimagnetic and antiferromagnetic insulators, magnonic transport studies in ferrimagnetic insulator heterostructures can provide valuable insights for their antiferromagnetic counterparts.  Nonlocal spin transport using lateral structures is ideal for investigating lateral magnonic transport.  Typically, a spin current is generated by a ferro-/ferri-magnetic (FM) or a heavy metal (HM) electrode in a nonlocal structure, which can be detected by another FM or HM electrode.  The Yang and Hammel groups reported a new nonlocal spin injection scheme using uniform-mode ferromagnetic resonance spin pumping in Pt/Y3Fe5O12 (YIG) lateral structures. This scheme is enabled by well-separated resonant fields of Pt/YIG and bare YIG due to substantial change of anisotropy in YIG films induced by a Pt overlayer, allowing for clearly distinguishable local and nonlocal spin pumping.  These results show that the spin decay length of nonlocal uniform-mode spin pumping in 20 nm YIG films is 2.1 μm at room temperature, opening up a new path for spin current generation, propagation, and detection for future spintronic application.

This work has been published in Nano Letters and can be accessed here.