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arXiv · 1405.4775

Enhancement of Pure Spin Currents in Spin Pumping Y3Fe5O12/Cu/metal Trilayers through Spin Conductance Matching

Abstract

Spin transport efficiency in heterostructures depends on the spin conductances of each constituent and their interfaces. We report a comparative study of spin pumping in Y3Fe5O12/Cu/Pt and Y3Fe5O12/Cu/W trilayers. Surprisingly, the insertion of a Cu interlayer between Y3Fe5O12 and W substantially improves (over a factor of 4) the spin current injection into W while similar insertion between Y3Fe5O12 and Pt degrades the spin current. This is a consequence of a much improved Y3Fe5O12/Cu spin mixing conductance relative to that for Y3Fe5O12/W. This result implies the possibility of engineered heterostructures with matching spin conductances to enable optimal spin transport efficiency.

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Chunhui Du, Hailong Wang, Fengyuan Yang, P. Chris Hammel. 2014-05-19. Enhancement of Pure Spin Currents in Spin Pumping Y3Fe5O12/Cu/metal Trilayers through Spin Conductance Matching. https://doi.org/10.1103/physrevapplied.1.044004

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