Research / 2020 / Article / Fig 5

Review Article

Recent Advances in Two-Dimensional Magnets: Physics and Devices towards Spintronic Applications

Figure 5

(a–e) Schematic illustrations of representative spintronic devices: spin valve (a), spin-orbit torque (b), spin field-effect transistor (c), spin-filter magnetic tunnel junction (d), and spin tunnel field-effect transistor (e). (f) Spin valve effect in a Fe3GeTe2 (~7 nm)/hBN/Fe3GeTe2 (~20 nm) with corresponding tunneling resistance and Hall resistance at 4.2 K with an applied field perpendicular to the layers. (g) Scheme of a magnetic tunnel junction based on 2D FeCl2 (top), 2D BN (middle), and 2D FeBr2 (bottom). (h) Spin gaps and Fermi levels of FeCl2, FeBr2, FeI2, BN, MoS2, black phosphorene (P), and graphene (C). (i) Measurement setup of spin-orbit torque (upper) and illustration of induced spin accumulation (lower) based on MoS2 or WSe2 (monolayer)/CoFeB (3 nm) at 300 K. (j) Scheme of the sample geometry of spin-orbit torque based on WTe2 (5.5 nm)/permalloy (6 nm) at room temperature. (k) Measurement setup and device configuration based on Cr2Ge2Te6 (50 nm)/tantalum (5 nm) spin-orbit torque. (l) The previous reported values of current density and in-plane field for spin-orbit torque switching. (m) Schematic diagram of the A-type antiferromagnetic in bilayer system with an electric field from layer 2 to layer 1. (n) Schematic spin-polarized current as a function of the gate voltage. (o) Schematic diagram of a spin tunnel field-effect transistor based on graphite (few-layer)/h-BN (~20 nm)/graphene (bilayer)/CrI3 (bilayer)/graphene (bilayer)/h-BN (~20 nm)/graphite (few-layer). (p) Gate-tunable tunneling conductance of a bilayer CrI3-based TFET at 2 K and 0.76 T. Panel (f) is reproduced with permission from ref. [60], copyright 2018 Nano Letters. Panels (g, h) are reproduced with permission from ref. [61], copyright 2017 Nano Letters. Panel (i) is reproduced with permission from ref. [64], copyright 2016 Nano Letters. Panel (j) is reproduced with permission from ref. [65], copyright 2016 Nature Physics. Panels (k, l) are reproduced with permission from ref. [66], copyright 2020 Advanced Materials. Panels (m, n) are reproduced with permission from ref. [67], copyright 2018 PNAS. Panels (o, p) are reproduced with permission from ref. [68], copyright 2019 Nature Electronics.