Atomic scale control of spin current transmission at interfaces

Abstract

Spin transmission at ferromagnet/heavy metal interfaces is of vital importance for many spintronic devices. Usually the spin current transmission is limited by the spin mixing conductance and loss mechanisms such as spin memory loss. In order to understand these effects, we study the interface transmission when an insulating interlayer is inserted between the ferromagnet and the heavy metal. For this we measure the inverse spin Hall voltage generated from optically injected spin current pulses as well as the magnitude of the spin pumping using ferromagnetic resonance.From our results we conclude that significant spin memory loss only occurs for 5d metals with less than half filled d -shell.

Impact of gigahertz and terahertz transport regimes on spin propagation and conversion in the antiferromagnet IrMn

“…In the thin AF limit, the layer behaves like a mono-exponential spin current attenuator in the ultrafast THz regime, 32,43 qualitatively same as in the established GHz experiments. 1,45 In the thick AF limit, when the ultrafast spin current does not reach the N layer, the role of IrMn as an attenuator changes to a converter, and the THz S2C efficiency signals saturate at very close averaged values as in the reference GHz measurements.…”