A Device Model for Achieving Sizable and Tunable Tunneling Magnetoresistance Using Two‐Dimensional Materials InX (X = O, Se) without Hetero‐Interface

The two‐dimensional (2D) materials InX (X = O, Se), experimentally available thus far, can become a ferromagnetic half metal under hole doping, though the charge neutral states of them are nonmagnetic semiconductors. Based on such an electronic characteristic, a theoretical model of magnetic tunnel junction (MTJ) is proposed composed only of one of the 2D InX. In doing so, the two semi‐infinite pieces of 2D InX in the half‐metallic state is assumed as the opposite electrodes which are separated by a strip of the same material but in its nonmagnetic state. Owing to the 2D nature of InX, the half metal electrodes of the InX device induced by hole doping can be achieved by using split gating technique. The numerical simulations identify a proper hole doping concentration, at which 100% tunneling magnetoresistance (TMR) ratios can be realized, accompanying an appreciable conductance of majority spin electron under parallel magnetization configuration. Under a finite bias voltage, the TMR ratio remains high. Therefore, the proposed device model is an ideal candidate for future spintronics applications. It enables electrical control of TMR and circumvents the detriment of hetero‐interface disorder inevitable in conventional MTJs. The two‐dimensional magnetic tunneling junction devices composed of InX (X = O, Se) not only avoid the detrimental effects of heterogeneous interface disorder but also exhibit a 100% tunneling magnetoresistance (TMR) ratios, with high TMR even under bias voltage. Additionally, the functionality of the magnetic tunneling junction can be controlled electronically to enable opening or closing.