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Self Consistent NEGF-LLG Model for Spin-Torque Based Devices

Sayeef Salahuddin·Supriyo Datta
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Abstract

We present here a self consistent solution of quantum transport, using the Non Equilibrium Green's Function (NEGF) method, and magnetization dynamics, using the Landau-Lifshitz-Gilbert (LLG) formulation. We have applied this model to study current induced magnetic switching due to `spin torque' in a device where the electronic transport is ballistic and the free magnetic layer is sandwiched between two anti-parallel ferromagnetic contacts. The device shows clear hysteretic current-voltage characteristics, at room temperature, with a sharp transition between the bistable states and hence can be used as a non-volatile memory. We show that the proposed design may allow reducing the switching current by an order of magnitude.

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Sayeef Salahuddin, Supriyo Datta. 2006-08-29. Self Consistent NEGF-LLG Model for Spin-Torque Based Devices. https://arxiv.org/abs/cond-mat/0606648

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