Giant magnetoresistance and tunneling electroresistance in multiferroic tunnel junctions with 2D ferroelectrics

Multiferroic tunneling junctions (MFTJs), composed of two magnetic electrodes separated by an ultrathin ferroelectric (FE) thin film as a barrier, have received great attention in multi-functional devices. Recent theoretical and experimental works have revealed that ferroelectric polarization exists at room temperature in two-dimensional ferroelectric (2D FE) materials within the ultrathin thickness. Here we propose a novel MFTJ Ni/bilayer In2Se3/BN/Ni, in which the resistance of the tunneling spin polarization electrons can be modulated by different magnetization alignments of the electrode and electric polarization direction of the 2D FE In2Se3 layer, leading to multiple tunneling resistance states. The tunneling magnetoresistance (TMR) and electroresistance (TER) of MFTJs are enhanced by the inserted h-BN layer, achieving an ON/OFF TER ratio of 4188% as well as a TMR ratio of 581% with a much lower resistance area. The giant tunneling resistance ratio, multiple resistance states, and ultra-low energy consumption in 2D FE-based MFTJs suggest their great potential in non-destructive non-volatile memories.

Automated summary

This study proposes a novel multiferroic tunneling junction that utilizes the electric polarization direction of the 2D ferroelectric material In2Se3 and the magnetization alignment of the electrodes to modulate resistance, achieving multiple resistance states. The inserted h-BN layer enhances both tunneling magnetoresistance and electroresistance, showing great potential in non-destructive non-volatile memories.