Spin Circuit Representation for Spin Pumping Phenomena

There has been enormous progress in the field of spintronics and nanomagnetics in recent years with the discovery of many new materials and phenomena and it remains a formidable challenge to integrate these phenomena into functional devices and evaluate their potential. To facilitate this process a modular approach has been proposed whereby different phenomena are represented by spin circuit components [1]. Unlike ordinary circuit components, these spin circuit components are characterized by 4-component voltages and currents (one for charge and three for spin). In this talk we will (1) present a spin circuit representation for spin pumping phenomena, (2) combine it with a spin circuit representation for the spin Hall effect [2] to show that it reproduces established results obtained earlier by other means, and finally (3) use it to propose a possible method for enhancing the spin pumping efficiency by an order of magnitude through the addition of a spin sink layer. [1] Kerem Camsari, Samiran Ganguly and Supriyo Datta, Modular Approach to Spintronics, https://nanohub.org/groups/spintronics [2] Seokmin Hong, Shehrin Sayed and Supriyo Datta, Spin Circuit Representation for the Spin Hall Effect, in review.