Multiferroic tunnel junctions (MFTJs) with tunneling electroresistance (TER) and tunneling magnetoresistance (TMR) effects have emerged as promising candidates for low-power and high-density information technology. However, simultaneously achieving giant TER and TMR ratios still faces significant hurdles. Here, we propose an MFTJ architecture that integrates ferroelectric bilayer-${\mathrm{Ga}}_2{\mathrm{O}}_3$ barrier and room-temperature ferromagnetic $2H-{\mathrm{VS}}_2$ electrodes with spin-valley-mismatch states. Within this structure, reversible Ohmic and Schottky contact switching at the ${\mathrm{VS}}_2/{\mathrm{Ga}}_2{\mathrm{O}}_3$ interfaces modulated by antiferroelectric phase transition can be realized by polarization-induced interlayer electron transfer. Crucially, the Ohmic contacts localize the electronic states of ${\mathrm{Ga}}_2{\mathrm{O}}_3$ layers near the Fermi level at the Γ points, leading to exclusive valley-matching with the spin-up states of ${\mathrm{VS}}_2$ and allowing the ${\mathrm{Ga}}_2{\mathrm{O}}_3$ layers to act as effective spin-valley-filtering layers. Moreover, the intrinsic spin-valley-mismatch states in the ${\mathrm{VS}}_2$ electrodes enable spin-valley matching to be tunable via parallel and antiparallel magnetic configurations. Accordingly, the designed ${\mathrm{VS}}_2$/bilayer-${\mathrm{Ga}}_2{\mathrm{O}}_3/{\mathrm{VS}}_2$ MFTJs achieve giant TER and TMR ratios up to $2.4\times {10}^4\%$ and $1.3\times {10}^8\%$, respectively, accompanied by 100% spin-valley-filtering effects and minimal resistance-area products of 0.09 Ω µ${\mathrm{m}}^2$. Our results propose a viable strategy for significantly improving the performance of MFTJs, enabling low-power and fast-response spintronic memory applications.

Close

PrevNext

View figure in article

• Ferroelectricity
• Ferromagnetism
• Spin filtering
• Tunneling electroresistance
• Tunneling magnetoresistance
• Valley degrees of freedom