Department of Physics, University of Virginia, Charlottesville, Virginia22904, United States.
Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, Virginia22904, United States.
ACS Nano. 2022 Dec 27;16(12):20222-20228. doi: 10.1021/acsnano.2c05645. Epub 2022 Dec 2.
The surface state of a 3D topological insulator (3DTI) is a spin-momentum locked conductive state, whose large spin hall angle can be used for the energy-efficient spin-orbit torque based switching of an overlying ferromagnet (FM). Conversely, the gated switching of the magnetization of a separate FM in or out of the TI surface plane can turn on and off the TI surface current. By exploiting this reciprocal behavior, we can use two FM/3DTI heterostructures to design an integrated 1-transistor 1-magnetic tunnel junction random access memory unit (1T1MTJ RAM) for an ultra low power Processing-in-Memory (PiM) architecture. Our calculation involves combining the Fokker-Planck equation with the Nonequilibrium Green Function (NEGF) based flow of conduction electrons and Landau-Lifshitz-Gilbert (LLG) based dynamics of magnetization. Our combined approach allows us to connect device performance metrics with underlying material parameters, which can guide proposed experimental and fabrication efforts.
三维拓扑绝缘体（3DTI）的表面态是一种自旋动量锁定的导电态，其大的自旋霍尔角可用于覆盖铁磁体（FM）的节能型基于自旋轨道扭矩的开关。相反，位于 TI 表面平面内或之外的单独 FM 的磁化的门控切换可以打开和关闭 TI 表面电流。通过利用这种互反行为，我们可以使用两个 FM/3DTI 异质结构来设计用于超低功耗处理内存储器（PiM）架构的集成 1 晶体管 1 磁隧道结随机存取存储器单元（1T1MTJ RAM）。我们的计算涉及将福克-普朗克方程与基于非平衡格林函数（NEGF）的传导电子流和基于朗道-利夫希茨-吉尔伯特（LLG）的磁化动力学相结合。我们的组合方法使我们能够将器件性能指标与基础材料参数联系起来，从而指导提出的实验和制造工作。
